Timeline of Major League Baseball
{{short description|None}}
{{Use mdy dates|date=May 2025}}
The following is a timeline of franchise evolution in Major League Baseball.
Background
:Source: {{cite book|title=The Baseball Encyclopedia|isbn=978-0028608150|publisher=Macmillan General Reference|edition=10|date=1996}}
:Note: Team names are given here according to the convention used by The Baseball Encyclopedia, which regularized them into the familiar form of modern team names. However, most teams in the early period had no name, aside from that of the club (as in "Hartford Base Ball Club" or "Athletic Base Ball Club of Philadelphia"), and nicknames like "Beaneaters," "Perfectos" and the many allusions to uniform colors were inventions by the florid sportswriters of the day.According to the National League's 1877 Constitution, the member clubs were given as "Boston B. B. Club, Chicago B. B. Club, Cincinnati B. B. Club, Hartford B. B. Club, Louisville B. B. Club, St. Louis B. B. Club." Constitution and Playing Rules of the National League of Professional Base Ball Clubs. Chicago, A. G. Spalding 1877.
The National Association of Base Ball Players (NABBP) was the first organization to govern baseball. The succeeding National Association of Professional Base Ball Players (NA) was then established as the first professional baseball league. In 1876 six clubs from the NA and two independents joined to create the National League (NL). In subsequent years, the following major leagues competed against the NL, but all eventually folded:
- American Association (AA) (1882–1891) – several franchises transferred to the NL, both during and after the AA's existence.
- Union Association (UA) (1884) – only one franchise joined the NL after the UA disbanded.
- Players' League (PL) (1890) – none of its franchises joined the NL.
In 1900 the minor league Western League renamed itself the American League (AL). All of the 1899 Western League teams were a part of the transformation with the Saint Paul Apostles moving to Chicago to play as the White Stockings. In 1901 the AL declared itself a major league. For its inaugural major league season the AL dropped its teams in Indianapolis, Buffalo and Minneapolis and replaced them with franchises in Boston, Philadelphia, and Baltimore. The Kansas City Blues moved to Washington D.C. to play as the Senators.
Another major league competitor was the Federal League (FL) (1914–1915). However, none of its teams joined either the NL or AL after it disbanded.
In 2020, Major League Baseball designated the following seven Negro leagues from 1920–1948 as major leagues:{{Cite web |title=MLB officially designates the Negro Leagues as 'Major League' |url=https://www.mlb.com/press-release/press-release-mlb-officially-designates-the-negro-leagues-as-major-league |access-date=2022-10-23 |website=MLB.com |language=en}}
- Negro National League I (NNL I) (1920–1931)
- Eastern Colored League (ECL) (1923–1928)
- American Negro League (ANL) (1929)
- East–West League (EWL) (1932)
- Negro Southern League (NSL) (1932)
- Negro National League II (NNL II) (1933–1948)
- Negro American League (NAL) (1937–1948)
Timeline
{{See also|Timeline of Negro league baseball teams#Graphical timeline}}
The first line is the formation of the National League (NL) in 1876, and the second is the transformation of the American League (AL) to a major league in 1901. The third line is the beginning of the expansion era in 1961. The fourth line marks the legal merger of the American and National Leagues into a single Major League Baseball in 2000.
World Series championships are shown with a "•", National League Pennants before the World Series are shown with a "^", and American League Pennants before the World Series are shown with a "#". No World Series was played in 1904, so the pennant winners for each league are indicated. Due to the 1994–95 Major League Baseball strike, there were no pennant or World Series winners in 1994, so this year is left blank.
- Prior to 1876, only teams from the National Association (NA) that established the NL are shown.
- Between 1876 and 1901, in addition to the NL teams, only American Association (AA) and Union Association (UA) teams that eventually joined the NL are shown. No teams from the Players' League (PL) are shown.
- After 1901, only AL and NL teams are shown. No teams from the Federal League (FL) nor the seven Negro leagues are shown.
{{Timeline Major League Baseball}}
1876–1900: Pre-modern Era
=1876: Founding of the National League (NL)=
The NL was established with eight teams.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FF91A4;"| Only season in NL § |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1876}} National League teams |
| Boston Red Caps |
| Chicago White Stockings
| style="background-color:#FF91A4;"| New York Mutuals§ |
| Cincinnati Reds
| style="background-color:#FF91A4;"| Philadelphia Athletics§ |
| Hartford Dark Blues |
=1877=
- The New York Mutuals and Philadelphia Athletics were expelled.
- The Hartford Dark Blues moved to Brooklyn and became the Brooklyn Hartfords.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FFC40C;"| Team folded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1877}} National League teams |
| Boston Red Caps |
| style="background-color:#FFC40C;"| Brooklyn Hartfords^
| style="background-color:#FFC40C;"| Louisville Grays^ |
| Chicago White Stockings
| style="background-color:#FFC40C;"| St. Louis Brown Stockings^ |
=1878=
- The Brooklyn Hartfords, Louisville Grays, and St. Louis Brown Stockings folded.
- The Indianapolis Blues, Milwaukee Grays, and Providence Grays joined.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NL * | style="background-color:#FF91A4;"| Only season in NL § |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1878}} National League teams |
| Boston Red Caps
| style="background-color:#FF91A4;"| Indianapolis Blues§ |
| Chicago White Stockings
| style="background-color:#FF91A4;"| Milwaukee Grays§ |
| Cincinnati Reds
| style="background-color:#00FF00;"| Providence Grays* |
=1879=
- The Indianapolis Blues and Milwaukee Grays folded.
- The Buffalo Bisons, Cleveland Blues, Syracuse Stars, and Troy Trojans joined.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NL * | style="background-color:#FF91A4;"| Only season in NL § | style="background-color:#FFC40C;"| Team disbanded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1879}} National League teams |
| Boston Red Caps
| style="background-color:#00FF00;"| Cleveland Blues* |
| style="background-color:#00FF00;"| Buffalo Bisons* |
| Chicago White Stockings
| style="background-color:#FF91A4;"| Syracuse Stars§ |
| style="background-color:#FFC40C;"| Cincinnati Reds^
| style="background-color:#00FF00;"| Troy Trojans* |
=1880=
- The Syracuse Stars folded.
- The Cincinnati Reds disbanded and were replaced by the Cincinnati Stars.
- The Worcester Worcesters joined.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NL * | style="background-color:#FF91A4;"| Only season in NL § |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1880}} National League teams |
| Boston Red Caps |
| Buffalo Bisons |
| Chicago White Stockings |
| style="background-color:#FF91A4;"| Cincinnati Stars§
| style="background-color:#00FF00;"| Worcester Worcesters* |
=1881=
- The Cincinnati Stars were expelled because they refused to sign a league-wide pledge to ban alcohol at ballparks.
- The Detroit Wolverines joined.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NL * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1881}} National League teams |
| Boston Red Caps
| style="background-color:#00FF00;"| Detroit Wolverines* |
| Buffalo Bisons |
| Chicago White Stockings |
| Cleveland Blues |
=1882: Establishment of the American Association (AA)=
The AA was established with six teams.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FFC40C;"| Team folded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1882}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA |
|---|
| style="background-color: #D0E7FF;"| Boston Red Caps
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #D0E7FF;"| Buffalo Bisons
|style="background-color: #FFCCCC;"| Cincinnati Red Stockings |
| style="background-color: #D0E7FF;"| Chicago White Stockings
|style="background-color: #FFCCCC;"| Louisville Eclipse |
| style="background-color: #D0E7FF;"| Cleveland Blues
|style="background-color: #FFCCCC;"| Philadelphia Athletics |
| style="background-color: #D0E7FF;"| Detroit Wolverines
|style="background-color: #FFCCCC;"| Pittsburgh Alleghenys |
| style="background-color: #D0E7FF;"| Providence Grays
|style="background-color: #FFCCCC;"| St. Louis Brown Stockings |
| style="background-color: #FFC40C;"| Troy Trojans^
|rowspan="2"| |
| style="background-color: #FFC40C;"| Worcester Worcesters^ |
=1883=
- The Troy Trojans and Worcester Worcesters folded.
- The New York Gothams and Philadelphia Quakers joined the NL.
- The Columbus Buckeyes and New York Metropolitans joined the AA.
- The Boston Red Caps became the Boston Beaneaters.
- The new St. Louis Brown Stockings became the St. Louis Browns.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NL or AA * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1883}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #D0E7FF;"| Buffalo Bisons
|style="background-color: #FFCCCC;"| Cincinnati Red Stockings |
| style="background-color: #D0E7FF;"| Chicago White Stockings
|style="background-color: #00FF00;"| Columbus Buckeyes* |
| style="background-color: #D0E7FF;"| Cleveland Blues
|style="background-color: #FFCCCC;"| Louisville Eclipse |
| style="background-color: #D0E7FF;"| Detroit Wolverines
|style="background-color: #00FF00;"| New York Metropolitans* |
| style="background-color: #00FF00;"| New York Gothams*
|style="background-color: #FFCCCC;"| Philadelphia Athletics |
| style="background-color: #00FF00;"| Philadelphia Quakers*
|style="background-color: #FFCCCC;"| Pittsburgh Alleghenys |
| style="background-color: #D0E7FF;"| Providence Grays
|style="background-color: #FFCCCC;"| St. Louis Browns |
=1884: The Union Association (UA) as a third league=
- The UA was established with eight teams.
- The Brooklyn Atlantics, Indianapolis Hoosiers, Toledo Blue Stockings, and Washington Nationals joined the AA.
- The Altoona Mountain Citys folded early-season and were replaced by the Kansas City Cowboys.
- The Washington Nationals from the AA folded mid-season and were replaced by the Richmond Virginians from Minor League Baseball.
- The Philadelphia Keystones folded mid-season and were replaced by the Wilmington Quicksteps from Minor League Baseball. The Quicksteps then folded late-season and were replaced by the Milwaukee Brewers, also from Minor League Baseball.
- The Chicago Browns moved to Pittsburgh and became the Pittsburgh Stogies, who folded late-season and were replaced by the St. Paul Saints.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in AA * | style="background-color:#FF91A4;"| Only season in AA/Folds mid-season § | style="background-color:#FFC40C;"| Last season in AA or NL ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1884}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA !UA |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |style="background-color: #FF91A4;"| Altoona Mountain Citys§ |
| style="background-color: #D0E7FF;"| Buffalo Bisons
|style="background-color: #00FF00;"| Brooklyn Atlantics* |
| style="background-color: #D0E7FF;"| Chicago White Stockings
|style="background-color: #FFCCCC;"| Cincinnati Red Stockings |
| style="background-color: #FFC40C;"| Cleveland Blues^
|style="background-color: #FFC40C;"| Columbus Buckeyes^ |style="background-color: #FF91A4;"| Chicago Browns/Pittsburgh Stogies§ |
| style="background-color: #D0E7FF;"| Detroit Wolverines
|style="background-color: #FF91A4;"| Indianapolis Hoosiers§ |
| style="background-color: #D0E7FF;"| New York Gothams
|style="background-color: #FFCCCC;"| Louisville Eclipse |
| style="background-color: #D0E7FF;"| Philadelphia Quakers
|style="background-color: #FFCCCC;"| New York Metropolitans |
| style="background-color: #D0E7FF;"| Providence Grays
|style="background-color: #FFCCCC;"| Philadelphia Athletics |style="background-color: #FF91A4;"| Philadelphia Keystones§ |
| rowspan="5"|
|style="background-color: #FFCCCC;"| Pittsburgh Alleghenys |
| style="background-color: #FF91A4;"| Richmond Virginians§ |
| style="background-color: #FFCCCC;"| St. Louis Browns |
| style="background-color: #FF91A4;"| Toledo Blue Stockings§
|style="background-color: #FF91A4;"| Wilmington Quicksteps§ |
| style="background-color: #FF91A4;"| Washington Nationals§
| |
=1885: Back to two leagues=
- The UA disbanded.
- The St. Louis Maroons from the UA joined the NL.
- The Cleveland Blues, Columbus Buckeyes, Indianapolis Hoosiers, and Toledo Blue Stockings folded.
- The Richmond Virginians returned to Minor League Baseball.
- The New York Gothams became the New York Giants.
- The Brooklyn Atlantics became the Brooklyn Grays.
- The Louisville Eclipse became the Louisville Colonels.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#99FF99;" | Team moved from the former UA ** | style="background-color:#FFC40C;"| Last season in NL ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1885}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #FFC40C;"| Buffalo Bisons^
|style="background-color: #FFCCCC;"| Brooklyn Grays |
| style="background-color: #D0E7FF;"| Chicago White Stockings
|style="background-color: #FFCCCC;"| Cincinnati Red Stockings |
| style="background-color: #D0E7FF;"| Detroit Wolverines
|style="background-color: #FFCCCC;"| Louisville Colonels |
| style="background-color: #D0E7FF;"| New York Giants
|style="background-color: #FFCCCC;"| New York Metropolitans |
| style="background-color: #D0E7FF;"| Philadelphia Quakers
|style="background-color: #FFCCCC;"| Philadelphia Athletics |
| style="background-color: #FFC40C;"| Providence Grays^
|style="background-color: #FFCCCC;"| Pittsburgh Alleghenys |
| style="background-color: #99FF99;"| St. Louis Maroons**
|style="background-color: #FFCCCC;"| St. Louis Browns |
=1886=
- The Buffalo Bisons transferred to Minor League Baseball.
- The Providence Grays folded.
- A new Kansas City Cowboys and Washington Nationals joined the NL.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NL * | style="background-color:#FF91A4;"| Only season in NL § |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1886}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #D0E7FF;"| Chicago White Stockings
|style="background-color: #FFCCCC;"| Brooklyn Grays |
| style="background-color: #D0E7FF;"| Detroit Wolverines
|style="background-color: #FFCCCC;"| Cincinnati Red Stockings |
| style="background-color: #FF91A4;"| Kansas City Cowboys§
|style="background-color: #FFCCCC;"| Louisville Colonels |
| style="background-color: #D0E7FF;"| New York Giants
|style="background-color: #FFCCCC;"| New York Metropolitans |
| style="background-color: #D0E7FF;"| Philadelphia Quakers
|style="background-color: #FFCCCC;"| Philadelphia Athletics |
| style="background-color: #D0E7FF;"| St. Louis Maroons
|style="background-color: #FFCCCC;"| Pittsburgh Alleghenys |
| style="background-color: #00FF00;"| Washington Nationals*
|style="background-color: #FFCCCC;"| St. Louis Browns |
=1887=
- The Kansas City Cowboys folded.
- The St. Louis Maroons moved to Indianapolis and became the Indianapolis Hoosiers.
- The Pittsburgh Alleghenys transferred to the NL.
- A new Cleveland Blues joined the AA.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in AA * | style="background-color:#99FF99;"| Team moved from AA ** | style="background-color:#FFC40C;"| Last season in AA ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1887}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #D0E7FF;"| Chicago White Stockings
|style="background-color: #FFCCCC;"| Brooklyn Grays |
| style="background-color: #D0E7FF;"| Detroit Wolverines
|style="background-color: #FFCCCC;"| Cincinnati Red Stockings |
| style="background-color: #D0E7FF;"| Indianapolis Hoosiers
|style="background-color: #00FF00;"| Cleveland Blues* |
| style="background-color: #D0E7FF;"| New York Giants
|style="background-color: #FFCCCC;"| Louisville Colonels |
| style="background-color: #D0E7FF;"| Philadelphia Quakers
|style="background-color: #FFC40C;"| New York Metropolitans^ |
| style="background-color: #99FF99;"| Pittsburgh Alleghenys**
|style="background-color: #FFCCCC;"| Philadelphia Athletics |
| style="background-color: #D0E7FF;"| Washington Nationals
|style="background-color: #FFCCCC;"| St. Louis Browns |
=1888=
- The Brooklyn Grays became the Brooklyn Bridegrooms.
- The New York Metropolitans folded.
- A new Kansas City Cowboys joined the AA.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in AA * | style="background-color:#FFC40C;"| Last season in NL ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1888}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #D0E7FF;"| Chicago White Stockings
|style="background-color: #FFCCCC;"| Brooklyn Bridegrooms |
| style="background-color: #FFC40C;"| Detroit Wolverines^
|style="background-color: #FFCCCC;"| Cincinnati Red Stockings |
| style="background-color: #D0E7FF;"| Indianapolis Hoosiers
|style="background-color: #FFCCCC;"| Cleveland Blues |
| style="background-color: #D0E7FF;"| New York Giants
|style="background-color: #00FF00;"| Kansas City Cowboys* |
| style="background-color: #D0E7FF;"| Philadelphia Quakers
|style="background-color: #FFCCCC;"| Louisville Colonels |
| style="background-color: #D0E7FF;"| Pittsburgh Alleghenys
|style="background-color: #FFCCCC;"| Philadelphia Athletics |
| style="background-color: #D0E7FF;"| Washington Nationals
|style="background-color: #FFCCCC;"| St. Louis Browns |
=1889=
- The Detroit Wolverines folded.
- The Cleveland Blues transferred to the NL and became the Cleveland Spiders.
- The Columbus Solons joined the AA.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in AA * | style="background-color:#99FF99;"| Team moved from AA ** | style="background-color:#FFC40C;"| Last season in AA or NL ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1889}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #D0E7FF;"| Chicago White Stockings
|style="background-color: #FFCCCC;"| Brooklyn Bridegrooms |
| style="background-color: #99FF99;"| Cleveland Spiders**
|style="background-color: #FFCCCC;"| Cincinnati Red Stockings |
| style="background-color: #FFC40C;"| Indianapolis Hoosiers^
|style="background-color: #00FF00;"| Columbus Solons* |
| style="background-color: #D0E7FF;"| New York Giants
|style="background-color: #FFC40C;"| Kansas City Cowboys^ |
| style="background-color: #D0E7FF;"| Philadelphia Quakers
|style="background-color: #FFCCCC;"| Louisville Colonels |
| style="background-color: #D0E7FF;"| Pittsburgh Alleghenys
|style="background-color: #FFCCCC;"| Philadelphia Athletics |
| style="background-color: #FFC40C;"| Washington Nationals^
|style="background-color: #FFCCCC;"| St. Louis Browns |
=1890: The Players' League (PL) as a third league=
- The PL was established with eight teams.
- The Chicago White Stockings became the Chicago Colts.
- The Philadelphia Quakers became the Philadelphia Phillies.
- The Brooklyn Bridegrooms transferred to the NL.
- The Cincinnati Red Stockings transferred to the NL and became the Cincinnati Reds.
- The Indianapolis Hoosiers, Kansas City Cowboys, and Washington Nationals folded.
- The Baltimore Orioles transferred to Minor League Baseball and were replaced by the Brooklyn Gladiators. The Brooklyn Gladiators then folded mid-season, and the Baltimore Orioles returned to the AA to finish the season.
- The Rochester Broncos, a new Syracuse Stars, and the Toledo Maumees joined the AA.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#99FF99;"| Team moved from AA ** | style="background-color:#FF91A4;"| Only season in AA § | style="background-color:#FFC40C;"| Last AA season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1890}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA !PL |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #99FF99;"| Brooklyn Bridegrooms**
|style="background-color: #FF91A4;"| Brooklyn Gladiators§ |
| style="background-color: #D0E7FF;"| Chicago Colts
|style="background-color: #FFCCCC;"| Columbus Solons |
| style="background-color: #99FF99;"| Cincinnati Reds**
|style="background-color: #FFCCCC;"| Louisville Colonels |
| style="background-color: #D0E7FF;"| Cleveland Spiders
|style="background-color: #FFC40C;"| Philadelphia Athletics^ |
| style="background-color: #D0E7FF;"| New York Giants
|style="background-color: #FF91A4;"| Rochester Broncos§ |
| style="background-color: #D0E7FF;"| Philadelphia Phillies
|style="background-color: #FFCCCC;"| St. Louis Browns |
| style="background-color: #D0E7FF;"| Pittsburgh Alleghenys
|style="background-color: #FF91A4;"| Syracuse Stars§ |
|
|style="background-color: #FF91A4;"| Toledo Maumees§ | |
=1891: Last AA season=
- The PL disbanded.
- The Brooklyn Bridegrooms became the Brooklyn Grooms.
- The Pittsburgh Alleghenys became the Pittsburgh Pirates.
- The Boston Reds from the PL joined the AA.
- The Philadelphia Athletics from the AA were expelled and replaced by the new Philadelphia Athletics from the PL.
- The Cincinnati Kelly's Killers joined the AA. They then folded mid-season and were replaced by the new Milwaukee Brewers from independent league Western Association.
- The Washington Statesmen joined the AA.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First MLB season * | style="background-color:#FF91A4;"| Only season in MLB § | style="background-color:#FFC40C;"| Last MLB season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1891}} major league teams |
| style="background-color: #99A8FF;"|NL
!style="background-color: #FF7B77;"|AA |
|---|
| style="background-color: #D0E7FF;"| Boston Beaneaters
|style="background-color: #FFCCCC;"| Baltimore Orioles |
| style="background-color: #D0E7FF;"| Brooklyn Grooms
|style="background-color: #FFC40C;"| Boston Reds^ |
| style="background-color: #D0E7FF;"| Chicago Colts
|style="background-color: #FF91A4;"| Cincinnati Kelly's Killers§ |
| style="background-color: #D0E7FF;"| Cincinnati Reds
|style="background-color: #FFC40C;"| Columbus Solons^ |
| style="background-color: #D0E7FF;"| Cleveland Spiders
|style="background-color: #FFCCCC;"| Louisville Colonels |
| style="background-color: #D0E7FF;"| New York Giants
|style="background-color: #FF91A4;"| Milwaukee Brewers§ |
| style="background-color: #D0E7FF;"| Philadelphia Phillies
|style="background-color: #FFC40C;"| Philadelphia Athletics^ |
| style="background-color: #D0E7FF;"| Pittsburgh Pirates
|style="background-color: #FFCCCC;"| St. Louis Browns |
|
|style="background-color: #00FF00;"| Washington Statesmen* |
=1892: NL monopoly=
- The AA folded.
- The Baltimore Orioles, Louisville Colonels, St. Louis Browns, and Washington Statesmen (all from the AA) joined the NL.
- The Washington Statesmen became the Washington Senators.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#99FF99;" | Teams move from the former AA ** |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1892}} to {{mlby|1895}} National League teams |
| style="background-color:#99FF99;"| Baltimore Orioles**
| style="background-color:#99FF99;"| Louisville Colonels** |
| Boston Beaneaters |
| Brooklyn Grooms |
| Chicago Colts |
| Cincinnati Reds
| style="background-color:#99FF99;"| St. Louis Browns** |
| Cleveland Spiders
| style="background-color:#99FF99;"| Washington Senators** |
=1896=
The Brooklyn Grooms became the Brooklyn Bridegrooms again.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1896}} to {{mlby|1897}} National League teams |
| Baltimore Orioles |
| Boston Beaneaters |
| Brooklyn Bridegrooms |
| Chicago Colts |
| Cincinnati Reds |
| Cleveland Spiders |
=1898=
The Chicago Colts became the Chicago Orphans.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1898}} National League teams |
| Baltimore Orioles |
| Boston Beaneaters |
| Brooklyn Bridegrooms |
| Chicago Orphans |
| Cincinnati Reds |
| Cleveland Spiders |
=1899=
- The Brooklyn Bridegrooms became the Brooklyn Superbas.
- The St. Louis Browns became the St. Louis Perfectos.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FFC40C;"| Team folded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1899}} National League teams |
| style="background-color:#FFC40C;"| Baltimore Orioles^
| style="background-color:#FFC40C;"| Louisville Colonels^ |
| Boston Beaneaters |
| Brooklyn Superbas |
| Chicago Orphans |
| Cincinnati Reds |
| style="background-color:#FFC40C;"| Cleveland Spiders^
| style="background-color:#FFC40C;"| Washington Senators^ |
=1900: Classic Eight=
- The Baltimore Orioles, Cleveland Spiders, Louisville Colonels, and Washington Senators folded.
- The St. Louis Perfectos became the St. Louis Cardinals.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1900}} National League teams |
| Boston Beaneaters |
| Brooklyn Superbas |
| Chicago Orphans |
| Cincinnati Reds |
1901–1919: Birth of the Modern Era
=1901: Founding of the American League (AL)=
The AL was established with eight teams.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1901}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Boston Beaneaters |
| style="background-color: #FFCCCC;"|Boston Americans
|style="background-color: #D0E7FF;"|Brooklyn Superbas |
| style="background-color: #FFCCCC;"|Chicago White Stockings
|style="background-color: #D0E7FF;"|Chicago Orphans |
| style="background-color: #FFCCCC;"|Cleveland Blues
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Milwaukee Brewers
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1902=
- The Milwaukee Brewers moved to St. Louis and became the St. Louis Browns.
- The Cleveland Blues became the Cleveland Bronchos
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FFC40C;"| Team folded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1902}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFC40C;"|Baltimore Orioles^
|style="background-color: #D0E7FF;"|Boston Beaneaters |
| style="background-color: #FFCCCC;"|Boston Americans
|style="background-color: #D0E7FF;"|Brooklyn Superbas |
| style="background-color: #FFCCCC;"|Chicago White Stockings
|style="background-color: #D0E7FF;"|Chicago Orphans |
| style="background-color: #FFCCCC;"|Cleveland Bronchos
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1903: National Agreement and Founding of National Baseball Commission=
- The NL and AL signed the National Agreement which formed the National Baseball Commission. They then promoted cooperation between the NL and AL.
- The new Baltimore Orioles folded.
- The New York Highlanders joined the AL.
- The Cleveland Bronchos became the Cleveland Naps.
- The Chicago Orphans became the Chicago Cubs.
- First World Series played between the AL and NL champions.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First AL season * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1903}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Americans
|style="background-color: #D0E7FF;"|Boston Beaneaters |
| style="background-color: #FFCCCC;"|Chicago White Stockings
|style="background-color: #D0E7FF;"|Brooklyn Superbas |
| style="background-color: #FFCCCC;"|Cleveland Naps
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #00FF00;"|New York Highlanders*
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1904=
The Chicago White Stockings became the Chicago White Sox.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1904}} to {{mlby|1906}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Americans
|style="background-color: #D0E7FF;"|Boston Beaneaters |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Superbas |
| style="background-color: #FFCCCC;"|Cleveland Naps
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Highlanders
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1907=
The Boston Beaneaters became the Boston Doves.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1907}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Americans
|style="background-color: #D0E7FF;"|Boston Doves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Superbas |
| style="background-color: #FFCCCC;"|Cleveland Naps
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Highlanders
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1908=
The Boston Americans became the Boston Red Sox.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1908}} to {{mlby|1910}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Doves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Superbas |
| style="background-color: #FFCCCC;"|Cleveland Naps
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Highlanders
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1911=
- The Boston Doves became the Boston Rustlers.
- The Brooklyn Superbas became the Brooklyn Trolley Dodgers.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1911}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Rustlers |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Trolley Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Naps
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Highlanders
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1912=
The Boston Rustlers became the Boston Braves.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1912}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Trolley Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Naps
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Highlanders
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1913=
- The New York Highlanders became the New York Yankees.
- The Brooklyn Trolley Dodgers became the Brooklyn Dodgers.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1913}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Naps
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1914: The Federal League (FL) as a third league=
- The Federal League (FL) declared itself as a "third major league" with its own eight teams, and competed with the NL and AL.
- The Brooklyn Dodgers became the Brooklyn Robins.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1914}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !FL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Naps
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1915=
- The Cleveland Naps became the Cleveland Indians.
- The Buffalo Buffeds became the Buffalo Blues.
- The Chicago Federals became the Chicago Whales.
- The new Indianapolis Hoosiers moved to Newark, New Jersey, and became the Newark Peppers.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1915}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !FL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1916: Back to two leagues=
The FL folded prior to the season.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1916}} to {{mlby|1919}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
1920–1946: Establishment of the Negro major leagues
=1920: Establishment of the Negro National League (NNL)=
The NNL was established with eight teams, the first black baseball league to be designated a major league.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FDDB6D;"| Team withdrew after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1920}} major league & 1920 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #FDDB6D;"|Dayton Marcos^^ |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1921: Commissioner of Baseball established=
- Following the fallout from the 1919 Black Sox Scandal, in November 1920, the National Baseball Commission was replaced by the Commissioner of Baseball, who acts as the chief executive officer of major and minor leagues.Frick, Ford. [https://books.google.com/books?id=crnl1c9JXGAC&pg=PA129 "Statement of Ford Frick – Commissioner of Baseball"]. In Sullivan, Dean A. (2002). Late Innings: A Documentary History of Baseball, 1945–1972, pp. 129–131. University of Nebraska Press. {{ISBN|0-8032-9285-6}}{{cite web|title=MLB Executives|publisher=Major League Baseball|year=2007|url=http://mlb.mlb.com/mlb/official_info/about_mlb/executives.jsp|access-date=2007-06-30}}
- The Dayton Marcos departed the NNL as an independent team.
- A new Columbus Buckeyes joined the NNL.
- The Cuban Stars became the Cincinnati Cuban Stars.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FF91A4;"| Only season in NNL § | style="background-color:#FFC40C;"| Team folded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1921}} major league & 1921 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |style="background-color: #FFC40C;"|Chicago Giants^ |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #FF91A4;"|Columbus Buckeyes§ |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1922=
- The Chicago Giants and Columbus Buckeyes folded.
- The Cleveland Tate Stars and Pittsburgh Keystones joined the NNL.
- The Cincinnati Cuban Stars became the Cuban Stars again.
- The St. Louis Giants became the St. Louis Stars.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NNL * | style="background-color:#FF91A4;"| Only season in NNL § |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1922}} major league & 1922 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |style="background-color: #00FF00;"|Cleveland Tate Stars* |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #FF91A4;"|Pittsburgh Keystones§ |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1923: Founding of the Eastern Colored League (ECL)=
- The ECL was established with six teams.
- The Pittsburgh Keystones folded.
- The Milwaukee Bears joined the NNL.
- The Cleveland Tate Stars departed from the NNL as an independent team and were replaced by the Toledo Tigers. The Toledo Tigers then folded mid-season, and the Cleveland Tate Stars returned to the NNL as an associate member to finish the season.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FF91A4;"| Only season in NNL § | style="background-color:#FFC9D3;"| Only season in NNL, folded mid-season §§ | style="background-color:#FFC40C;"| Associate member, joined mid-season, team folded after season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1923}} major league & 1923 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL !ECL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FF91A4;"|Milwaukee Bears§ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |rowspan="3"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #FFC9D3;"|Toledo Tigers§§ |
| |
|style="background-color: #FFC40C;"|Cleveland Tate Stars^ |
=1924=
- The Milwaukee Bears folded.
- The Birmingham Black Barons and Cleveland Browns joined the NNL.
- The Harrisburg Giants and Washington Potomacs joined the ECL.
- The Indianapolis ABCs temporarily dropped out for the season in June and were replaced by the Memphis Red Sox.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NNL or ECL* | style="background-color:#FF91A4;"| Only season in NNL § |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1924}} major league & 1924 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL !ECL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |style="background-color: #00FF00;"|Birmingham Black Barons* |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FF91A4;"|Cleveland Browns§ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #00FF00;"|Harrisburg Giants* |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #00FF00;"|Memphis Red Sox* |style="background-color: #00FF00;"|Washington Potomacs* |
| |
| |
=1925=
- The Cleveland Browns folded.
- The Indianapolis ABCs returned to the NNL.
- The Washington Potomacs moved to Wilmington, Delaware and became the Wilmington Potomacs and then folded mid-season.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FFC40C;"| Team folded mid-season ^ | style="background-color:#FDDB6D;"| Team withdrew after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1925}} major league & 1925 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL !ECL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |style="background-color: #FDDB6D;"|Birmingham Black Barons^^ |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #FDDB6D;"|Memphis Red Sox^^ |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #FFC40C;"|Wilmington Potomacs^ |
=1926=
- The Cleveland Elites joined the NNL and folded mid-season.
- The Dayton Marcos returned to the NNL and departed mid-season as an independent team.
- The Newark Stars joined the ECL and folded mid-season.
- The Birmingham Black Barons and Memphis Red Sox departed the NNL and joined Minor League Baseball's Negro Southern League (NSL).
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FF91A4;"| Only season in NNL or ECL, folded mid-season § | style="background-color:#FFC40C;"| Team folded after this season ^ | style="background-color:#FDDB6D;"| Last season in NNL, withdrew mid-season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1926}} major league & 1926 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL !ECL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |style="background-color: #FF91A4;"|Cleveland Elites§ |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FDDB6D;"|Dayton Marcos^^ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FFC40C;"|Indianapolis ABCs^ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color:#FF91A4;"|Newark Stars§ |
=1927=
- The Indianapolis ABCs folded.
- The Birmingham Black Barons and Memphis Red Sox returned to the NNL.
- The Cleveland Hornets joined the NNL.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#99FF99;"| Team rejoined from minor league Negro Southern League ** | style="background-color:#FF91A4;"| Only season in NNL § | style="background-color:#FFC40C;"| Last season in NNL or ECL ^ | style="background-color:#FDDB6D;"| Team departed after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1927}} major league & 1927 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL !ECL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |style="background-color: #99FF99;"|Birmingham Black Barons** |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FF91A4;"|Cleveland Hornets§ |style="background-color: #FFC40C;"|Brooklyn Royal Giants^ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #FFC40C;"|Harrisburg Giants^ |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FDDB6D;"|Hilldale Club^^ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #99FF99;"|Memphis Red Sox** |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=1928: Last ECL season=
- The Cleveland Hornets folded.
- The Brooklyn Royal Giants, Harrisburg Giants, and Hilldale Club withdrew from the ECL as independent teams.
- The Cleveland Tigers joined the NNL.
- The Philadelphia Tigers joined the ECL.
- The ECL then disbanded mid-season.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in MLB * | style="background-color:#FF91A4;"| Only season in NNL or ECL § | style="background-color:#FFC40C;"| Last MLB season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1928}} major league & 1928 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL !ECL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FF91A4;"|Cleveland Tigers§ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #FF91A4;"|Philadelphia Tigers§ |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |rowspan="3"| |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1929: American Negro League (ANL)'s only season=
- The ANL was established with six teams. Five of those teams were from the ECL. The independent Homestead Grays also joined the ECL.
- The Cleveland Tigers folded.
- The Philadelphia Tigers folded.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FFC40C;"| Team folded after this season ^ | style="background-color:#FDDB6D;"| Team independent after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1929}} major league & 1929 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL !ANL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |style="background-color: #FFC40C;"|Atlantic City Bacharach Giants^ |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |style="background-color: #FDDB6D;"|Baltimore Black Sox^^ |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FFC40C;"|Cuban Stars (East)^ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #FDDB6D;"|Hilldale Club^^ |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #FDDB6D;"|Homestead Grays^^ |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FDDB6D;"|New York Lincoln Giants^^ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=1930=
- The Atlantic City Bacharach Giants and the Cuban Stars from the ANL folded.
- The Baltimore Black Sox, Hilldale Club, Homestead Grays, and New York Lincoln Giants became independent teams.
- The ANL disbanded.
- The Louisville Black Caps and Nashville Elite Giants joined the NNL.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NNL * | style="background-color:#FFC40C;"| Team folded after this season ^ | style="background-color:#FDDB6D;"| Team departed after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1930}} major league & 1930 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |style="background-color: #FDDB6D;"|Birmingham Black Barons^^ |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FFC40C;"|Cuban Stars^ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #FDDB6D;"|Kansas City Monarchs^^ |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #00FF00;"|Louisville Black Caps* |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #FDDB6D;"|Memphis Red Sox^^ |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #00FF00;"|Nashville Elite Giants* |
| | |
=1931: Last NNL season=
- The Cuban Stars folded.
- The Birmingham Black Barons, Memphis Red Sox, and Nashville Elite Giants departed the NNL and joined the NSL.
- The Kansas City Monarchs departed the NNL as an independent team (though remains loosely associated with the league).
- The Cleveland Cubs and a new Indianapolis ABCs joined the NNL.
- The Chicago American Giants became the Chicago Columbia Giants.
- The Louisville Black Caps became the Louisville White Sox.
- The NNL disbanded mid-season; although, teams continued to play each other as independent teams.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NNL * | style="background-color:#FFC40C;"| Team folded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1931}} major league & 1931 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Robins |style="background-color: #00FF00;"|Cleveland Cubs |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FFC40C;"|Detroit Stars^ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #00FF00;"|Indianapolis ABCs* |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FFC40C;"|St. Louis Stars^ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1932: Negro Southern League (NSL)'s only major league season and East–West League (EWL)'s only season=
- The Brooklyn Robins became the Brooklyn Dodgers again.
- The Detroit Stars and St. Louis Stars folded.
- The Cleveland Cubs moved back to Nashville, Tennessee and became the Nashville Elite Giants again.
- The EWL was established with eight teams. Three of those teams, the Baltimore Black Sox, Hilldale Club, and Homestead Grays were from the ANL.
- The NSL was considered a major league for the season with 10 teams. Five of those teams, the Birmingham Black Barons, Chicago Columbia Giants, Indianapolis ABCs, Memphis Red Sox, and Nashville Elite Giants were from the NNL.
- The Chicago Columbia Giants became the Chicago American Giants again.
- The Newark Browns departed mid-season as an independent team.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#99FF99;"| Team rejoined MLB ** | style="background-color:#FF91A4;"| Only season in MLB § | style="background-color:#FFC40C;"| Team folded after this season ^ | style="background-color:#FDDB6D;"| Team departed after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1932}} major league & 1932 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NSL !EWL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves | style="background-color: #FDDB6D;" |Atlanta Black Crackers^^ | style="background-color: #99FF99;" |Baltimore Black Sox** |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers | style="background-color: #FDDB6D;" |Birmingham Black Barons^^ | style="background-color: #FF91A4;" |Cleveland Stars§ |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs | style="background-color: #99FF99;" |Chicago American Giants** | style="background-color: #FF91A4;" |Detroit Wolves§ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds | style="background-color: #99FF99;" |Indianapolis ABCs** | style="background-color: #FFC40C;" |Hilldale Club^ |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants | style="background-color: #FF91A4;" |Little Rock Grays§ | style="background-color: #FDDB6D;" |Homestead Grays^^ |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies | style="background-color: #FFC40C;" |Louisville Black Caps/Columbus Turf Club^ | style="background-color: #FF91A4;" |Newark Browns§ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates | style="background-color: #FDDB6D;" |Memphis Red Sox^^ | style="background-color: #FF91A4;" |Pollock's Cuban Stars§ |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals | style="background-color: #FF91A4;" |Monroe Monarchs§ | style="background-color: #FF91A4;" |Washington Pilots§ |
| rowspan="2"|
|rowspan="2"| | style="background-color: #FF91A4;" |Montgomery Grey Sox§ | rowspan="2" | |
| style="background-color: #99FF99;"|Nashville Elite Giants** |
=1933: Establishment of the second NNL=
- The Little Rock Grays and Columbus Turf Club folded.
- The Atlanta Black Crackers and Birmingham Black Barons withdrew as independent teams.
- The NSL was demoted to minor league status.
- The Cleveland Stars, Detroit Wolves, Hilldale Club, and Newark Browns folded.
- Pollock's Cuban Stars and the Washington Pilots withdrew as independent teams.
- The Baltimore Black Sox became the Baltimore Sox.
- The EWL disbanded.
- The second NNL was established with 7 teams. Five of those teams, the Baltimore Sox, Chicago American Giants, Homestead Grays, Indianapolis ABCs, and Nashville Elite Giants were from the NSL or EWL.
- The Pittsburgh Crawfords joined the NNL.
- The Indianapolis ABCs moved mid-season to Detroit, Michigan and became the Detroit Stars.
- The Columbus Blue Birds joined the NNL. The team disbanded and merged with the independent Akron Black Tyrites after the first half of the split season. The Akron Black Tyrites joined the NNL in place of the Columbus Blue Birds as the Akron Grays before they moved to Cleveland, Ohio and became the Cleveland Giants for one game.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NNL * | style="background-color:#99FF99;"| Team moved from former EWL or NSL ** | style="background-color:#FF91A4;"| Only season in NNL, folded mid-season § | style="background-color:#FFC9D3;"| Only season in NNL, joined mid-season §§ | style="background-color:#FFC40C;"| Team folded after this season ^ | style="background-color:#FDDB6D;"| Team departed after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1933}} major league & 1933 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |style="background-color: #FFC9D3;"|Akron Grays/Cleveland Giants§§^ |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |style="background-color: #99FF99;"|Baltimore Sox** |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #99FF99;"|Chicago American Giants** |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #FF91A4;"|Columbus Blue Birds§ |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #FDDB6D;"|Homestead Grays^^ |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FFC40C;"|Indianapolis ABCs/Detroit Stars^ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #99FF99;"|Nashville Elite Giants** |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #00FF00;"|Pittsburgh Crawfords* |
=1934=
- The Cleveland Giants and Detroit Stars folded.
- The Homestead Grays withdrew as an independent team.
- The Cleveland Red Sox, Newark Dodgers, Philadelphia Bacharach Giants, and Philadelphia Stars joined the NNL.
- The Baltimore Sox became the Baltimore Black Sox again.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NNL * | style="background-color:#FF91A4;"| Only season in NNL § | style="background-color:#FFC40C;"| Team folded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1934}} major league & 1934 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |style="background-color: #FFC40C;"|Baltimore Black Sox^ |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FF91A4;"|Cleveland Red Sox§ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #00FF00;"|Newark Dodgers* |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FF91A4;"|Philadelphia Bacharach Giants§ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #00FF00;"|Philadelphia Stars* |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1935=
- The Cleveland Red Sox folded.
- The Baltimore Black Sox and Philadelphia Bacharach Giants withdrew as independent teams.
- The Brooklyn Eagles and New York Cubans joined the NNL.
- The Homestead Grays returned to the NNL.
- The Nashville Elite Giants moved to Columbus, Ohio and became the Columbus Elite Giants.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NNL * | style="background-color:#99FF99;"| Team rejoined MLB ** | style="background-color:#FF91A4;"| Only season in NNL § | style="background-color:#FFC40C;"| Team folded after this season ^ | style="background-color:#FDDB6D;"| Team departed after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1935}} major league & 1935 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |style="background-color: #FF91A4;"|Brooklyn Eagles§ |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |style="background-color: #FDDB6D;"|Chicago American Giants^^ |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #99FF99;"|Homestead Grays** |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #00FF00;"|New York Cubans* |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FFC40C;"|Newark Dodgers^ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1936=
- The Boston Braves became the Boston Bees.
- The Chicago American Giants withdrew.
- The Brooklyn Eagles and Newark Dodgers merged and became the Newark Eagles.
- The New York Black Yankees joined the NNL.
- The Columbus Elite Giants moved to Washington, D.C. and became the Washington Elite Giants.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NNL * | style="background-color:#FDDB6D;"| Team departed after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1936}} major league & 1936 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Bees |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |style="background-color: #00FF00;"|New York Black Yankees* |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FDDB6D;"|New York Cubans^^ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #00FF00;"|Newark Eagles* |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=1937: Founding of the Negro American League (NAL)=
- The NAL was established with eight teams. Four of those teams, the Birmingham Black Barons, Chicago American Giants, Kansas City Monarchs, and Memphis Red Sox were previously from the NSL or the first NNL.
- The New York Cubans withdrew.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#99FF99;"| Team rejoined MLB ** | style="background-color:#FF91A4;"| Only season in NAL § |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1937}} major league & 1937 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Bees |style="background-color: #99FF99;"|Birmingham Black Barons** |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |style="background-color: #99FF99;"|Chicago American Giants** |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FF91A4;"|Cincinnati Tigers§ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #FF91A4;"|Detroit Stars§ |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #FF91A4;"|Indianapolis Athletics§ |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #99FF99;"|Kansas City Monarchs** |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #99FF99;"|Memphis Red Sox** |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #FF91A4;"|St. Louis Stars§ |
=1938=
- The Cincinnati Tigers, the new Detroit Stars, the Indianapolis Athletics, and the new St. Louis Stars folded.
- The Atlanta Black Crackers, a new Indianapolis ABCs, and the Jacksonville Red Caps joined the NAL.
- The Washington Black Senators joined the NNL.
- The Washington Elite Giants moved to Baltimore, Maryland and became the Baltimore Elite Giants.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NAL * | style="background-color:#99FF99;"| Team rejoined MLB ** | style="background-color:#FF91A4;"| Only season in NNL § | style="background-color:#FDDB6D;"| Team departed after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1938}} major league & 1938 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Bees |style="background-color: #99FF99;"|Atlanta Black Crackers** |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |style="background-color: #FDDB6D;"|Birmingham Black Barons^^ |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #00FF00;"|Indianapolis ABCs* |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |style="background-color: #00FF00;"|Jacksonville Red Caps* |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #FF91A4;"|Washington Black Senators§ |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals | | |
=1939=
- The Washington Black Senators folded.
- The Birmingham Black Barons withdrew.
- The New York Cubans returned to the NNL.
- The Indianapolis ABCs moved to St. Louis, Missouri and became the St. Louis Stars.
- The Atlanta Black Crackers moved to Indianapolis, Indiana and became the Indianapolis ABCs.
- The Jacksonville Red Caps moved to Cleveland, Ohio and became the Cleveland Bears.
- The Pittsburgh Crawfords moved to Toledo, Ohio and became the Toledo Crawfords.
- The Toledo Crawfords withdrew and joined the NAL mid-season.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#99FF99;"| Team joined NAL or rejoined NNL ** | style="background-color:#FFC40C;"| Team folded after this season ^ | style="background-color:#FDDB6D;"| Team left NNL mid-season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1939}} major league & 1939 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Bees |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #FFC40C;"|Indianapolis ABCs^ |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #99FF99;"|New York Cubans** |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #99FF99;"|Toledo Crawfords** |style="background-color: #FDDB6D;"|Toledo Crawfords^^ |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals | | |
=1940=
- The Indianapolis ABCs folded.
- The Birmingham Black Barons returned to the NAL.
- The St. Louis Stars split their home games between St. Louis, Missouri and New Orleans, Louisiana and became the St. Louis–New Orleans Stars.
- The Toledo Crawfords split their home games between Toledo, Ohio and Indianapolis, Indiana and became the Toledo–Indianapolis Crawfords.{{Cite web |last=sabr |title=Kings of the Hill: The Story of the Pittsburgh Crawfords – Society for American Baseball Research |url=https://sabr.org/research/article/kings-of-the-hill-the-story-of-the-pittsburgh-crawfords/ |access-date=2024-04-30 |language=en-US}}
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#99FF99;"| Team rejoined NAL ** | style="background-color:#FFC40C;"| Team folded after this season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1940}} major league & 1940 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Bees |style="background-color: #99FF99;"|Birmingham Black Barons** |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #FFC40C;"|Toledo–Indianapolis Crawfords^ |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=1941=
- The Boston Bees became the Boston Braves again.
- The Toledo–Indianapolis Crawfords folded.
- The Cleveland Bears moved back to Jacksonville, Florida and became the Jacksonville Red Caps again.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#FDDB6D;"| Team temporarily folded after this season ^^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1941}} major league & 1941 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #FDDB6D;"|St. Louis–New Orleans Stars^^ |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |rowspan="2"| |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1942=
- The Philadelphia Phillies became the Philadelphia Phils.
- The St. Louis–New Orleans Stars disbanded.
- The Cincinnati–Cleveland Buckeyes joined the NAL.
- The Jacksonville Red Caps departed mid-season.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NAL * | style="background-color:#FFC40C;"| Team left mid-season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1942}} major league & 1942 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #00FF00;"|Cincinnati–Cleveland Buckeyes* |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #FFC40C;"|Jacksonville Red Caps^ |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phils |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |rowspan="2"| |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1943=
- The Philadelphia Phils became the Philadelphia Phillies again.
- The St. Louis–New Orleans Stars reformed and joined the NNL as the Harrisburg–St. Louis Stars, since they moved to Harrisburg, Pennsylvania; although, they kept the St. Louis moniker as a part of their name. The team proceeded to withdraw in July to barnstorm, and then they folded.
- The Cincinnati–Cleveland Buckeyes left Cincinnati, Ohio and became the Cleveland Buckeyes.
- The Cincinnati Clowns joined the NAL.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| First season in NAL * | style="background-color:#FFC40C;"| Team folds mid-season ^ |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1943}} major league & 1943 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |style="background-color: #FFC40C;"|Harrisburg–St. Louis Stars^ |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #00FF00;"|Cincinnati Clowns* |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=1944=
The Cincinnati Clowns split their home games between Cincinnati, Ohio and Indianapolis, Indiana and became the Cincinnati–Indianapolis Clowns, though would play more games in Indianapolis beginning in 1946.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1944}} to {{mlby|1946}} major league & 1944 to 1946 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |rowspan="2"| |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
1947–1960: Integration, end of the Negro major leagues, and relocations
{{Main|Baseball color line|Major League Baseball relocations of 1950s–1960s}}
=1947=
The Brooklyn Dodgers, Cleveland Indians, and St. Louis Browns integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1947}} major league & 1947 Negro major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Boston Braves† |
| style="background-color: #FFCCCC;"|Chicago White Sox†
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs† |
| style="background-color: #FFCCCC;"|Detroit Tigers†
|style="background-color: #D0E7FF;"|Cincinnati Reds† |
| style="background-color: #FFCCCC;"|New York Yankees†
|style="background-color: #D0E7FF;"|New York Giants† |
| style="background-color: #FFCCCC;"|Philadelphia Athletics†
|style="background-color: #D0E7FF;"|Philadelphia Phillies† |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates† |rowspan="2"| |rowspan="2"| |
| style="background-color: #FFCCCC;"|Washington Senators†
|style="background-color: #D0E7FF;"|St. Louis Cardinals† |
=1948=
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † | style="background-color:#FFC40C;"| Team folded after this season ^ |
- The Cincinnati–Indianapolis Clowns stopped playing in Cincinnati, Ohio and permanently played in Indianapolis, Indiana and became the Indianapolis Clowns.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1948}} major league & 1948 Negro major league teams |
| style="background-color: #FF7B77;" |AL
! style="background-color: #99A8FF;" |NL !NAL !NNL |
|---|
| style="background-color: #FFCCCC;" |Boston Red Sox†
| style="background-color: #D0E7FF;" |Boston Braves† |
| style="background-color: #FFCCCC;" |Chicago White Sox†
| style="background-color: #D0E7FF;" |Brooklyn Dodgers |
| style="background-color: #FFCCCC;" |Cleveland Indians
| style="background-color: #D0E7FF;" |Chicago Cubs† | style="background-color: #FFC40C;" |New York Black Yankees^ |
| style="background-color: #FFCCCC;" |Detroit Tigers†
| style="background-color: #D0E7FF;" |Cincinnati Reds† |
| style="background-color: #FFCCCC;" |New York Yankees†
| style="background-color: #D0E7FF;" |New York Giants† |
| style="background-color: #FFCCCC;" |Philadelphia Athletics†
| style="background-color: #D0E7FF;" |Philadelphia Phillies† |
| style="background-color: #FFCCCC;" |St. Louis Browns
| style="background-color: #D0E7FF;" |Pittsburgh Pirates† | rowspan="2" | | rowspan="2" | |
| style="background-color: #FFCCCC;" |Washington Senators†
| style="background-color: #D0E7FF;" |St. Louis Cardinals† |
=1949=
- The New York Black Yankees folded.
- Due to the ongoing process of integration, the NAL lost its major league status.
- The NNL folded.
- All of the NNL teams, except for the newly independent Homestead Grays joined the NAL.
- The New York Giants integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1949}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Boston Braves† |
| style="background-color: #FFCCCC;"|Chicago White Sox†
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs† |
| style="background-color: #FFCCCC;"|Detroit Tigers†
|style="background-color: #D0E7FF;"|Cincinnati Reds† |
| style="background-color: #FFCCCC;"|New York Yankees†
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics†
|style="background-color: #D0E7FF;"|Philadelphia Phillies† |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates† |
| style="background-color: #FFCCCC;"|Washington Senators†
|style="background-color: #D0E7FF;"|St. Louis Cardinals† |
=1950=
The Boston Braves integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1950}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox†
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs† |
| style="background-color: #FFCCCC;"|Detroit Tigers†
|style="background-color: #D0E7FF;"|Cincinnati Reds† |
| style="background-color: #FFCCCC;"|New York Yankees†
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics†
|style="background-color: #D0E7FF;"|Philadelphia Phillies† |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates† |
| style="background-color: #FFCCCC;"|Washington Senators†
|style="background-color: #D0E7FF;"|St. Louis Cardinals† |
=1951=
The Chicago White Sox integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1951}} to {{mlby|1952}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Boston Braves |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Chicago Cubs† |
| style="background-color: #FFCCCC;"|Detroit Tigers†
|style="background-color: #D0E7FF;"|Cincinnati Reds† |
| style="background-color: #FFCCCC;"|New York Yankees†
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics†
|style="background-color: #D0E7FF;"|Philadelphia Phillies† |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates† |
| style="background-color: #FFCCCC;"|Washington Senators†
|style="background-color: #D0E7FF;"|St. Louis Cardinals† |
=1953: Braves relocation to Milwaukee, and Cincinnati renaming=
- The Boston Braves moved to Milwaukee and became the Milwaukee Braves.
- The Cincinnati Reds became the Cincinnati Redlegs.
- The Chicago Cubs, Philadelphia Athletics, and Pittsburgh Pirates integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1953}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Cincinnati Redlegs† |
| style="background-color: #FFCCCC;"|Detroit Tigers†
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|New York Yankees†
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies† |
| style="background-color: #FFCCCC;"|St. Louis Browns
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators†
|style="background-color: #D0E7FF;"|St. Louis Cardinals† |
=1954: Browns relocation to Baltimore=
- The St. Louis Browns moved to Baltimore and became the Baltimore Orioles.
- The Cincinnati Redlegs, St. Louis Cardinals, and Washington Senators integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1954}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Cincinnati Redlegs |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|Detroit Tigers†
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|New York Yankees†
|style="background-color: #D0E7FF;"|Philadelphia Phillies† |
| style="background-color: #FFCCCC;"|Philadelphia Athletics
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1955: Athletics relocation to Kansas City=
- The Philadelphia Athletics moved to Kansas City, Missouri, and became the Kansas City Athletics.
- The New York Yankees integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1955}} to {{mlby|1956}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Cincinnati Redlegs |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|Detroit Tigers†
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Kansas City Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies† |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1957=
The Philadelphia Phillies integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1957}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Brooklyn Dodgers |
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Cincinnati Redlegs |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|Detroit Tigers†
|style="background-color: #D0E7FF;"|New York Giants |
| style="background-color: #FFCCCC;"|Kansas City Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
=1958: The NL exits New York for California=
- The Brooklyn Dodgers moved to Los Angeles and became the Los Angeles Dodgers.
- The New York Giants moved to San Francisco and became the San Francisco Giants.
- The Detroit Tigers integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| | Team has yet to integrate † |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1958}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Boston Red Sox†
|style="background-color: #D0E7FF;"|Cincinnati Redlegs |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|Kansas City Athletics
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|San Francisco Giants |
=1959: Cincinnati reverts back to the Reds=
- The Cincinnati Redlegs became the Cincinnati Reds again.
- The Boston Red Sox integrated.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1959}} to {{mlby|1960}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|Kansas City Athletics
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|San Francisco Giants |
1961–1968: First expansion
=1961 Relocation and AL expansion=
{{Main|1961 Major League Baseball expansion}}
- The Washington Senators moved to the Minneapolis–Saint Paul area and became the Minnesota Twins.
- The Los Angeles Angels and a new Washington Senators joined the AL.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| 1961 expansion team * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1961}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|Kansas City Athletics
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #00FF00;"|Los Angeles Angels*
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
| style="background-color: #FFCCCC;"|Minnesota Twins
|style="background-color: #D0E7FF;"|San Francisco Giants |
| style="background-color: #FFCCCC;"|New York Yankees
|rowspan="2"| |
| style="background-color: #00FF00;"|Washington Senators* |
=1962: NL expansion=
{{Main|1962 Major League Baseball expansion}}
- The Houston Colt .45s and New York Mets joined the NL.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| 1962 expansion team * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1962}} to {{mlby|1964}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #00FF00;"|Houston Colt .45s* |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|Kansas City Athletics
|style="background-color: #00FF00;"|New York Mets* |
| style="background-color: #FFCCCC;"|Los Angeles Angels
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|Minnesota Twins
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|San Francisco Giants |
=1965: Houston and Angels renaming=
- The Houston Colt .45s became the Houston Astros.
- The Los Angeles Angels became the California Angels on September 2, 1965, with 28 games left in the season.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1965}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Los Angeles/California Angels
|style="background-color: #D0E7FF;"|Houston Astros |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Milwaukee Braves |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|New York Mets |
| style="background-color: #FFCCCC;"|Kansas City Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|Minnesota Twins
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|San Francisco Giants |
=1966: Braves relocation to Atlanta=
The Milwaukee Braves moved to Atlanta and became the Atlanta Braves.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1966}} to {{mlby|1967}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Atlanta Braves |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|California Angels
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Houston Astros |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|New York Mets |
| style="background-color: #FFCCCC;"|Kansas City Athletics
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|Minnesota Twins
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|San Francisco Giants |
=1968: Athletics relocation to Oakland=
The Kansas City Athletics moved to Oakland, California, and became the Oakland Athletics.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1968}} major league teams |
| style="background-color: #FF7B77;"|AL
!style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #D0E7FF;"|Atlanta Braves |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #D0E7FF;"|Chicago Cubs |
| style="background-color: #FFCCCC;"|California Angels
|style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Chicago White Sox
|style="background-color: #D0E7FF;"|Houston Astros |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #D0E7FF;"|New York Mets |
| style="background-color: #FFCCCC;"|Minnesota Twins
|style="background-color: #D0E7FF;"|Philadelphia Phillies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #D0E7FF;"|Pittsburgh Pirates |
| style="background-color: #FFCCCC;"|Oakland Athletics
|style="background-color: #D0E7FF;"|St. Louis Cardinals |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #D0E7FF;"|San Francisco Giants |
1969–1993: Birth of division play
=1969: Expansion and realignment=
{{Main|1969 Major League Baseball expansion}}
- The Kansas City Royals and Seattle Pilots joined the AL.
- The Montreal Expos and San Diego Padres joined the NL.
- The two leagues each realigned into two six-team divisions
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| 1969 expansion team * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1969}} major league teams |
| colspan="2" style="background-color: #FF7B77;"|AL
!colspan="2" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|California Angels |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Atlanta Braves |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #00FF00;"|Montreal Expos* |style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #00FF00;"|Kansas City Royals* |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #00FF00;"|San Diego Padres* |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #00FF00;"|Seattle Pilots* |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |
=1970: Pilots relocation to Milwaukee=
The Seattle Pilots moved to Milwaukee and became the Milwaukee Brewers.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1970}} to {{mlby|1971}} major league teams |
| colspan="2" style="background-color: #FF7B77;"|AL
!colspan="2" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|California Angels |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Atlanta Braves |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #D0E7FF;"|Montreal Expos |style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #FFCCCC;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Washington Senators
|style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |
=1972: Senators relocation to the Dallas–Fort Worth metroplex=
- The Washington Senators moved to Arlington, Texas, in the Dallas–Fort Worth metroplex and became the Texas Rangers.
- The Texas Rangers and Milwaukee Brewers switched divisions.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1972}} to {{mlby|1976}} major league teams |
| colspan="2" style="background-color: #FF7B77;"|AL
!colspan="2" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|California Angels |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Atlanta Braves |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #D0E7FF;"|Montreal Expos |style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Milwaukee Brewers
|style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |
=1977: AL expansion=
{{Main|1977 Major League Baseball expansion}}
- The Seattle Mariners joined the AL West.
- The Toronto Blue Jays joined the AL East.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| 1977 expansion team * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1977}} to {{mlby|1992}} major league teams |
| colspan="2" style="background-color: #FF7B77;"|AL
!colspan="2" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|California Angels |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Atlanta Braves |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #D0E7FF;"|Montreal Expos |style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Milwaukee Brewers
|style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #00FF00;"|Seattle Mariners* |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |
| style="background-color: #00FF00;"|Toronto Blue Jays*
|style="background-color: #FFCCCC;"|Texas Rangers |colspan="2"| |
=1993: NL expansion=
{{Main|1993 Major League Baseball expansion}}
- The Colorado Rockies joined the NL West.
- The Florida Marlins joined the NL East.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| 1993 expansion team * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1993}} major league teams |
| colspan="2" style="background-color: #FF7B77;"|AL
!colspan="2" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|California Angels |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Atlanta Braves |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #00FF00;"|Florida Marlins* |style="background-color: #D0E7FF;"|Cincinnati Reds |
| style="background-color: #FFCCCC;"|Cleveland Indians
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #D0E7FF;"|Montreal Expos |style="background-color: #00FF00;"|Colorado Rockies* |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |
| style="background-color: #FFCCCC;"|Milwaukee Brewers
|style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |
1994–present: Wild Card era
=1994: Realignment=
MLB realigned to three divisions in each league to accommodate an expanded postseason format with a wild card team (although this new playoff format would not be fully implemented until 1995 due to a work stoppage):
- The AL Central was formed with the Cleveland Indians and Milwaukee Brewers transferring from the AL East, and the Chicago White Sox, Kansas City Royals, and Minnesota Twins transferring from the AL West.
- The NL Central was formed with the Chicago Cubs, Pittsburgh Pirates, and St. Louis Cardinals transferring from the NL East, and the Cincinnati Reds and Houston Astros transferring from the NL West.
- The Atlanta Braves transferred to the NL East.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1994}} to {{mlby|1996}} major league teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|California Angels |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Florida Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Montreal Expos |style="background-color: #D0E7FF;"|Houston Astros |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Milwaukee Brewers |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Francisco Giants |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins | |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=1997: Angels renaming=
The California Angels became the Anaheim Angels.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1997}} major league teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Anaheim Angels |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Florida Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Detroit Tigers
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Montreal Expos |style="background-color: #D0E7FF;"|Houston Astros |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Milwaukee Brewers |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Francisco Giants |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins | |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=1998: Expansion =
{{Main|1998 Major League Baseball expansion}}
- The Arizona Diamondbacks joined the NL West.
- The Tampa Bay Devil Rays joined the AL East.
- The Detroit Tigers transferred to the AL Central.
- To continue intraleague-only play throughout most of the season, the Milwaukee Brewers transferred to the NL Central so both leagues would have an even number of teams.
| class="wikitable" style="font-size:100%;line-height:1.1;"
| style="background-color:#00FF00;"| 1998 expansion team * |
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|1998}} to {{mlby|1999}} major league teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Anaheim Angels |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #00FF00;"|Arizona Diamondbacks* |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Florida Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Montreal Expos |style="background-color: #D0E7FF;"|Houston Astros |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #00FF00;"|Tampa Bay Devil Rays*
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins | |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Francisco Giants |
| colspan="4"|
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=2000: Legal merger of AL & NL into MLB=
- The AL and NL merged and formed Major League Baseball.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|2000}} to {{mlby|2004}} Major League Baseball teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Anaheim Angels |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Arizona Diamondbacks |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Florida Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Montreal Expos |style="background-color: #D0E7FF;"|Houston Astros |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Tampa Bay Devil Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins | |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Francisco Giants |
| colspan="4"|
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=2001: Scrapped contraction to 28 teams=
{{See also|2001 Major League Baseball contraction plan}}
In 2001, MLB team owners voted 28–2 to eliminate two teams, the Minnesota Twins and the Montreal Expos for the 2002 season. In this realignment:
- Texas Rangers would move to the AL Central
- Arizona Diamondbacks would move to the AL West
- Pittsburgh Pirates would move to the NL East
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ Planned league realignment for the 2002 Major League Baseball season |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Anaheim Angels |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Arizona Diamondbacks |style="background-color: #D0E7FF;"|Florida Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Tampa Bay Devil Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|San Francisco Giants |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Texas Rangers | |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|St. Louis Cardinals | |
By December 2001, this plan was scrapped; both teams would be retained for the following season.
=2005: Expos relocation and Angels renaming=
- The Montreal Expos moved to Washington, D.C. and became the Washington Nationals.
- The Anaheim Angels became the Los Angeles Angels of Anaheim.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|2005}} to {{mlby|2007}} Major League Baseball teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Los Angeles Angels of Anaheim |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Arizona Diamondbacks |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Florida Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Tampa Bay Devil Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins | |style="background-color: #D0E7FF;"|Washington Nationals |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Francisco Giants |
| colspan="4"|
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=2008: Tampa Bay renaming=
The Tampa Bay Devil Rays became the Tampa Bay Rays.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|2008}} to {{mlby|2011}} Major League Baseball teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Los Angeles Angels of Anaheim |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Arizona Diamondbacks |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Florida Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Tampa Bay Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins | |style="background-color: #D0E7FF;"|Washington Nationals |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Francisco Giants |
| colspan="4"|
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=2012: Marlins renaming=
The Florida Marlins became the Miami Marlins.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|2012}} Major League Baseball teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Los Angeles Angels of Anaheim |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Arizona Diamondbacks |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|Miami Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Houston Astros |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Tampa Bay Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins | |style="background-color: #D0E7FF;"|Washington Nationals |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Francisco Giants |
| colspan="4"|
|style="background-color: #D0E7FF;"|St. Louis Cardinals | |
=2013: Astros switch leagues=
With interleague play expanded to occur throughout the season, the Houston Astros transferred to the AL West to accommodate each league with 15 clubs apiece.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|2013}} to {{mlby|2015}} Major League Baseball teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Houston Astros |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Arizona Diamondbacks |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Los Angeles Angels of Anaheim |style="background-color: #D0E7FF;"|Miami Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Tampa Bay Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|Washington Nationals |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |
=2016: Angels renaming=
The Los Angeles Angels of Anaheim became the Los Angeles Angels.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|2016}} to {{mlby|2021}} Major League Baseball teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Houston Astros |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Arizona Diamondbacks |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Indians |style="background-color: #FFCCCC;"|Los Angeles Angels |style="background-color: #D0E7FF;"|Miami Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Tampa Bay Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|Washington Nationals |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |
=2022: Cleveland renaming=
The Cleveland Indians became the Cleveland Guardians.
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|2022}} to {{mlby|2024}} Major League Baseball teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Houston Astros |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Arizona Diamondbacks |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Guardians |style="background-color: #FFCCCC;"|Los Angeles Angels |style="background-color: #D0E7FF;"|Miami Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Oakland Athletics |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Tampa Bay Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|Washington Nationals |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |
=2025: Athletics relocation=
The Oakland Athletics temporarily moved to West Sacramento, California, and branded themselves as simply the "Athletics" and "A's" with no city name attached, until they permanently relocate to Las Vegas in 2028 or later when their new ballpark is completed.{{cite web|url=https://www.nytimes.com/athletic/5391365/2024/04/04/oakland-athletics-sacramento-ballpark-agreement-2025/|title=Oakland A's to play in Sacramento's Sutter Health Park beginning in 2025 ahead of move to Las Vegas|first1=Evan|last1=Drellich|first2=Ken|last2=Rosenthal|website=The Athletic|date=April 4, 2024|url-access=subscription}}
| class="wikitable" style="font-size:100%;line-height:1.1;"
|+ {{mlby|2025}} to present Major League Baseball teams |
| colspan="3" style="background-color: #FF7B77;"|AL
!colspan="3" style="background-color: #99A8FF;"|NL |
|---|
| style="background-color: #FFA7A7;"|East
!style="background-color: #FFA7A7;"|Central !style="background-color: #FFA7A7;"|West !style="background-color: #B7D0FF;"|East !style="background-color: #B7D0FF;"|Central !style="background-color: #B7D0FF;"|West |
| style="background-color: #FFCCCC;"|Baltimore Orioles
|style="background-color: #FFCCCC;"|Chicago White Sox |style="background-color: #FFCCCC;"|Athletics |style="background-color: #D0E7FF;"|Atlanta Braves |style="background-color: #D0E7FF;"|Chicago Cubs |style="background-color: #D0E7FF;"|Arizona Diamondbacks |
| style="background-color: #FFCCCC;"|Boston Red Sox
|style="background-color: #FFCCCC;"|Cleveland Guardians |style="background-color: #FFCCCC;"|Houston Astros |style="background-color: #D0E7FF;"|Miami Marlins |style="background-color: #D0E7FF;"|Cincinnati Reds |style="background-color: #D0E7FF;"|Colorado Rockies |
| style="background-color: #FFCCCC;"|New York Yankees
|style="background-color: #FFCCCC;"|Detroit Tigers |style="background-color: #FFCCCC;"|Los Angeles Angels |style="background-color: #D0E7FF;"|New York Mets |style="background-color: #D0E7FF;"|Milwaukee Brewers |style="background-color: #D0E7FF;"|Los Angeles Dodgers |
| style="background-color: #FFCCCC;"|Tampa Bay Rays
|style="background-color: #FFCCCC;"|Kansas City Royals |style="background-color: #FFCCCC;"|Seattle Mariners |style="background-color: #D0E7FF;"|Philadelphia Phillies |style="background-color: #D0E7FF;"|Pittsburgh Pirates |style="background-color: #D0E7FF;"|San Diego Padres |
| style="background-color: #FFCCCC;"|Toronto Blue Jays
|style="background-color: #FFCCCC;"|Minnesota Twins |style="background-color: #FFCCCC;"|Texas Rangers |style="background-color: #D0E7FF;"|Washington Nationals |style="background-color: #D0E7FF;"|St. Louis Cardinals |style="background-color: #D0E7FF;"|San Francisco Giants |