May 1918

• The Egyptian Expeditionary Force captured the towns of Sunet Nimrun and Es Salt in Jordan but faced counterattacks from Ottoman and German forces.{{cite book |title=Military Operations Egypt & Palestine from June 1917 to the End of the War |last=Falls |first=Cyril |series=Official History of the Great War Based on Official Documents by Direction of the Historical Section of the Committee of Imperial Defence |author2=A. F. Beck |year=1930 |volume=2 Part 1 |publisher=HM Stationery Office |location=London|oclc=644354483|pages=379–380}}
• Battle of Lahti – The Red Guards fled their garrison at Hennala, ending the battle at Lahti, Finland. Some 30,000 Reds Guards and their supporters surrendered to the White Guards and the support German detachment force.{{cite book| last=Takala| first=Hannu| date=1998| title=Taistelu Lahdesta 1918| location=Lahti| publisher=Lahti City Museum| pages=61–88| isbn=951-84948-2-7}}
• The Royal Air Force established air squadron No. 252.{{cite web|title=History of 252 Squadron| url=https://www.raf.mod.uk/history/252squadron.cfm| website=Royal Air Force| access-date=13 December 2017}}
• The Kyung Sung Public Agricultural College was founded, the precursor to the University of Seoul.{{cite web|title=History - About UOS| url=http://www.uos.ac.kr/en/about/aboutHis.do| website=University of Seoul| access-date=2 December 2017}}
• The Independent Voters Association was established as a conservative counterpart to the more socialist-leaning Nonpartisan League in North Dakota.{{cite book| title=The Future of American Politics| publisher=Anchor Press| author=Lubell, Samuel| year=1956| pages=145–147| edition=2nd|ol = 6193934M}}
• Born: Jack Paar, American TV personality, host of The Tonight Show from 1957 to 1962; in Canton, Ohio, United States (d. 2004){{citation needed|date=March 2025}}
• Died: Grove Karl Gilbert, 74, American geologist, discoverer of the Meteor Crater in Arizona (b. 1843){{citation needed|date=March 2025}}

• Vyborg massacre – News of the murder of hundreds of Red Guard prisoners and civilians by White Guard militia in Vyborg, Finland reached White Guard commander Carl Gustaf Emil Mannerheim, He ordered an immediate investigation.{{cite book| last1=Westerlund| first1=Lars| title=Venäläissurmat Suomessa 1914–22: Osa 2.2. Sotatapahtumat 1918–22| chapter=Me odotimme teitä vapauttajina ja te toitte kuolemaa – Viipurin valloituksen yhteydessä teloitetut venäläiset| year=2004| publisher=Prime Minister's Office of Finland| isbn=952-5354-45-8| page=155}}
• German submarine {{SMU|UB-31||6}} was sunk by depth charges from three Royal Navy ships with the loss of all 22 crew.{{cite book| last1=Gröner| first1=Erich| last2=Jung| first2=Dieter| last3=Maass| first3=Martin| translator-last1=Thomas| translator-first1=Keith| translator-last2=Magowan| translator-first2=Rachel| year=1991| title=U-boats and Mine Warfare Vessels| volume=2| work=German Warships 1815–1945| location=London| publisher=Conway Maritime Press| isbn=0-85177-593-4|pages=23–25}}
• Died: Jüri Vilms, 29, Estonian politician, first deputy prime minister of Estonia; executed (b. 1889){{citation needed|date=March 2025}}

File:Vyborg massacre 1918.jpg in Finland.]]

• Vyborg massacre – Finnish commander Carl Gustaf Emil Mannerheim sent a telegram to the town commandant in Vyborg, Finland with an order to stop the massacre of Red Guard prisoners and ethnic Russians civilians in the town. In all, by the time the violence stopped, 1,200 people had been shot dead, including more than 800 Red Guard prisoners and between 360 and 420 civilians of Russian or affiliated ethnicity.Westerlund 2004, p. 155
• Battle of Ahvenkoski – With the Kymi Valley now the last stronghold for the Red Guards in Finland, negotiations for surrender began with the Germans.{{cite book|last=Vainio|first=Seppo|date=2010|title=Poliittiset väkivaltaisuudet Itä-Uudellamaalla 1917–18|location=Vantaa|publisher=Seppo Vainio|pages=69|isbn=978-952-92766-5-3}}
• The Soviet Red Army established the 6th Rifle Division in Gdov, Russia.{{Cite book|script-title=ru:Вооруженные силы СССР после Второй Мировой войны: от Красной Армии к Советской|last1 = Feskov|first1 = V.I.|last2 = Golikov|first2 = V.I.|last3 = Kalashnikov|first3 = K.A.|last4 = Slugin|first4 = S.A.|publisher = Tomsk University Press|year = 2013|isbn = 9785895035306|volume = 1 Land Forces|location = Tomsk|language = ru|trans-title = The Armed Forces of the USSR after World War II: From the Red Army to the Soviet|page=565}}
• Official war artist William Orpen opened his exhibition War in London and later donated the paintings to the British government. He was knighted in June.{{cite book|editor-first=HCG |editor-last=Matthew |editor-first2=Brian |editor-last2=Harrison |publisher=Oxford University Press |year=2004 |title=Oxford Dictionary of National Biography |volume=41 (Norbary-Osborn) |isbn=0-19-861391-1}}
• New Zealand writer Katherine Mansfield married her long-time partner John Middleton Murry at the Kensington register office in London.{{cite journal|url=http://www.nzetc.org/tm/scholarly/tei-Whi071Kota-t1-g1-t8.html|title=Katherine Mansfield, 1888–1923|author=Joanna Woods|publisher=Victoria University of Wellington|journal= Kōtare: New Zealand Notes & Queries |year=2007|volume=7 |issue=1 |doi=10.26686/knznq.v7i1.776 |access-date=13 October 2008|doi-access=free}}
• The University of the Philippines Cebu was established in Cebu, Philippines{{cite web|title=About UP Cebu| url=http://upcebu.edu.ph/about-up-cebu/| website=UPCebu| publisher=University of the Philippines Cebu| access-date=3 December 2017}} along with a preparatory school for students entering university.{{cite web| title=UP High School – Cebu| url=http://upcebu.edu.ph/social-sciences/up-high-school-cebu/| website=UPCebu| date=17 July 2013|publisher=University of the Philippines Cebu| access-date=3 December 2017}}
• Born:
• Richard Dudman, American journalist, member of the editorial staff for the St. Louis Post-Dispatch for over thirty years; in Centerville, Iowa, United States (d. 2017){{citation needed|date=March 2025}}
• Ted Bates, English football player, forward for Southampton from 1937 to 1953 and manager from 1955 to 1973; as Edric Thornton Bates, in Thetford, England (d. 2003){{citation needed|date=March 2025}}
• Mona Inglesby, British ballet dancer and choreographer, director of International Ballet; as Mona Vredenburg, in London, England (d. 2006){{citation needed|date=March 2025}}
• Died:
• Derwas Cumming, 26, Australian football player, forward for the Perth Football Club from 1907 to 1910, 1914 and Melbourne University Football Club from 1911 to 1912, recipient of the Military Cross; died from wounds sustained at the Second Battle of Villers-Bretonneux (b. 1891){{citation needed|date=March 2025}}
• John Chase, 61, American army medical officer, commander of the Colorado National Guard during the Colorado Labor Wars and the Ludlow Massacre (b. 1856){{citation needed|date=March 2025}}

• The Egyptian Expeditionary Force retreated back to the Jordan Valley after failing to hold the towns of Sunet Nimrun and Es Salt, suffering 1,784 casualties while inflicting over 2,000 on the Ottomans.Falls 1930 Vol. 2, pp. 385–386
• Soviet Russia established the Belomorsky, North Caucasus, and Volga Military Districts.Soviet Military Encyclopedia, vol. 6, pp. 524–525Russian Ministry of Defence,[http://www.mil.ru/848/1045/1272/1365/1366/8796/index.shtml History of the North Caucasus Military District] {{Webarchive|url=https://web.archive.org/web/20070929102744/http://www.mil.ru/848/1045/1272/1365/1366/8796/index.shtml |date=2007-09-29 }}, www.mil.ru, accessed August 17, 2007Feskov 2013, p. 429
• The Senate of Finland was re-established in Vaasa, Finland.{{Citation| last1=Keränen| first1=Jorma| last2=Tiainen| first2=Jorma| last3=Ahola| first3=Matti| last4=Ahola| first4=Veikko| last5=Frey| first5=Stina| last6=Lempinen| first6=Jorma| last7=Ojanen| first7=Eero| last8=Paakkonen| first8=Jari| last9=Talja| first9=Virpi| last10=Väänänen| first10=Juha| year=1992| title=Suomen itsenäistymisen kronikka| place=Jyväskylä| publisher=Gummerus| isbn=951-20-3800-5| pages=123–137}}
• Baseball Ontario was established as the provincial governing body of the sport in Hamilton, Ontario.{{cite web| url=http://www.baseballontario.com/filestore/htmleditattachedfiles/2010%20Constitution%20No%20Ads%20for%20Web2010-03-09T15-36-11v001_by_292.pdf| title=Constitution & By-Laws of Baseball Ontario| access-date=2010-06-18| publisher=Baseball Ontario}}
• Born: Kakuei Tanaka, Japanese state leader, 40th Prime Minister of Japan; in Nishiyama, Niigata, Empire of Japan (present-day Japan) (d. 1993){{citation needed|date=March 2025}}
• Died: Howard Burnham, 46, American engineer and spy, collected intelligence for France while conducting mining surveying work in the Alps during World War I, brother to Frederick Russell Burnham (b. 1870){{citation needed|date=March 2025}}

File:Irish Conscription 1918 John Dillon Roscommon Rally.jpg speaks from a platform at an anti-conscription rally in County Roscommon, Ireland.]]

• Battle of Ahvenkoski – The final force Red Guards of Finland surrendered at Ahvenkoski, Finland, with 800 soldiers laying down their arms to the German detachment force in Finland. The battle became the final military action of the Finnish Civil War.Vainio 2010, p. 69
• An estimated 15,000 people attended an anti-conscription meeting in County Roscommon, Ireland, where John Dillon, leader of the Irish Parliamentary Party, and Éamon de Valera of Sinn Féin shared the platform in a united cause against conscription.{{cite web|url = http://www.independent.ie/regionals/droghedaindependent/localnotes/the-mystery-of-the-sinn-fin-film-27108094.html | publisher = Independent News & Media | title = The mystery of the Sinn Féin film | date = 15 October 2004}}
• German submarine {{SMU|UB-119||6}} was rammed and sunk in the Atlantic Ocean, killing all 34 crew.{{cite web |url=http://uboat.net/wwi/boats/index.html?boat=UB+119 |title=UB 119 |publisher=Uboat.net |access-date=16 November 2012}}
• German submarine {{SMU|UB-70||6}} disappeared after being seen in the Mediterranean Sea east of Gibraltar, with all 33 crew lost.{{cite web |url=http://uboat.net/wwi/boats/index.html?boat=UB+70 |title=UB 70|publisher=Uboat.net |access-date=11 November 2012}}
• The United States Army established the 1st Pursuit Group to support the American Expeditionary Forces on the Western Front.Series "C", Vol. 9, History of the 1st Pursuit Group. Gorrell's History of the American Expeditionary Forces Air Service, 1917-1919, National Archives, Washington, D.C. via {{cite web|url=http://www.fold3.com |title=Fold3 - Historical military records |access-date=2013-03-06 |url-status=live |archive-url=https://web.archive.org/web/20161226013201/https://www.fold3.com/ |archive-date=26 December 2016 |df=dmy }}
• Mary Pickford starred in M'Liss, a remake of a 1915 film. It was directed by Marshall Neilan and adapted by screenwriter Frances Marion from the short story by Bret Harte.[https://web.archive.org/web/20110520115400/http://movies.nytimes.com/movie/120026/M-Liss/overview The New York Times Review] Remakes[http://www.silentera.com/PSFL/data/M/Mliss1918.html Progressive Silent Film List: M'Liss] at silentera.com
• The village of Galahad, Alberta was established.{{cite web | url=http://www.municipalaffairs.alberta.ca/cfml/MunicipalProfiles/index | title=Location and History Profile: Village of Galahad | publisher=Alberta Municipal Affairs | date=December 25, 2015 | access-date=January 1, 2016}}
• Born: Egidio Galea, Maltese clergy, member of the Catholic resistance to Nazi Germany during World War II; in Birgu, Malta (d. 2005){{citation needed|date=March 2025}}

• Nicaragua declared war on the Central Powers.{{cite web |url=https://www.loc.gov/law/help/digitized-books/world-war-i-declarations/foreign.php#U |title=World War: Declarations of War from Around the World|publisher=Library of Congress}}{{cite web |url=http://www.firstworldwar.com/features/declarationsofwar.htm |title=Who Declared War and When|publisher = Firstworldwar.com}}
• The Don Cossacks under command of Pyotr Krasnov captured Rostov-on-Don in what was then the Don Soviet Republic, allowing German forces to occupy the city two days later. The area was later incorporated into the Don Republic.{{Cite book |title=Historical Dictionary of the Russian Civil Wars, 1916-1926 |last=Smele |first=Jonathan D. |date=2015 |publisher=Rowman & Littlefield |isbn=9781442252813 |location=London |page=337 |url=https://books.google.com/books?id=QwquCgAAQBAJ&pg=PA337}}
• The United States Navy established the Coco Solo naval station near Cativá, Panama as part of the defense of the Panama Canal.{{cite book |last=Van Wyen |first=Adrian O. |title =Naval Aviation in World War I |url=https://archive.org/details/navalaviationinw00wash |publisher =Chief of Naval Operations |date =1969 |location =Washington, D.C. |page =[https://archive.org/details/navalaviationinw00wash/page/64 64] }}
• Born:
• Eva Kolstad, Norwegian politician and activist, promoter of women's rights in Norway and internationally, 18th Norwegian Association for Women's Rights, member of the United Nations Commission on the Status of Women from 1969 to 1975; as Eva Severine Lundegaard Hartvig, in Haldar, Norway (d. 1999){{citation needed|date=March 2025}}
• Zayed bin Sultan Al Nahyan, Arabic noble and state leader, first President of the United Arab Emirates; in Abu Dhabi, Trucial States (present-day United Arab Emirates) (d. 2004){{citation needed|date=March 2025}}

• Romania signed a treaty with the Central Powers to end its involvement with World War I but it was never ratified as Romanian monarch King Ferdinand refused to sign it. It was nullified when an armistice was signed with Germany on November 11.Kitchen, Martin "Hindenburg, Ludendorff and Rumania" pp. 214-222 from The Slavonic and East European Review, Volume 54, Issue # 2, April 1976, p. 223

• The first Muslim-Christian Association met in Jaffa, Palestine.Pappe, Ilan (2002) The Rise and Fall of a Palestinian Dynasty. The Husaynis 1700–1948. AL Saqi edition 2010. {{ISBN|978-0-86356-460-4}}. p. 175
• German submarine {{SMU|U-32| Germany |6}} was depth charged and sunk in the Mediterranean Sea north west of Malta by a Royal Navy ship with all 41 crew killed.{{cite book| last1=Gröner| first1=Erich| last2=Jung| first2=Dieter| last3=Maass| first3=Martin| translator-last1=Thomas| translator-first1=Keith| translator-last2=Magowan| translator-first2=Rachel| year=1991| title=U-boats and Mine Warfare Vessels| volume=2| work=German Warships 1815–1945| location=London| publisher=Conway Maritime Press| isbn=0-85177-593-4| page=6}}
• Born: Ptolemy Reid, Guyanese state leader, second Prime Minister of Guyana; in Dartmouth, British Guiana (present-day Guyana) (d. 2003){{citation needed|date=March 2025}}

File:Field Marshal Sir John French 2.jpg John French]]

• The Royal Navy failed in their second attempt to seal off the German U-boat base at Ostend, Germany despite using the destroyer HMS Vindictive as a blockship.{{Cite book| author=Geoffrey Bennett| title=Naval Battles of the First World War| year=1968| publisher=Penguin| isbn=0-14-139087-5| pages=276–278}}
• Liberal Party leader H. H. Asquith took up allegations of the British War Cabinet misleading Parliament about troop strengths on the Western Front from a letter published in the press on May 7 by Major-General Frederick Maurice of the British Army. The fierce debate in the House of Commons led to Prime Minister David Lloyd George refuting the claims and treating the issue as a vote of confidence, allowing him to win the debate and tip perception against Asquith as not being an effective wartime leader. The resulting vote was in favor of government support 295 votes to 108, although about half of the Members of Parliament were absent as they were serving in the war.Gooch, John. "The Maurice Debate 1918," Journal of Contemporary History (1968) 3#4 pp. 211–228 [https://www.jstor.org/stable/259859 in JSTOR]Cook, Chris. A Short History of the Liberal Party: 1900–1992; Macmillan, 1993 p.73
• Field Marshal John French was appointed Lord Lieutenant of Ireland and Supreme Commander of the British Army in Ireland.{{cite web|url=http://www.kcl.ac.uk/lhcma/locreg/FRENCH.shtml|title=French, Sir John Denton Pinkstone, (1852–1925), 1st Earl of Ypres, Field Marshal|publisher=Liddell Hart Centre for Military Archives|access-date=2012-08-24}}
• Germany conducted the first heavier-than-air raid on England since March, sending four Riesenfluzeuge bombers to Dover. High winds over the North Sea forced the squadron to turn back only to find their bases shrouded in fog. Only one landed safely, with the other three being destroyed in crashes.Fredette, Raymond H., The Sky on Fire: The First Battle of Britain 1917–1918, New York: Harvest, 1976, {{ISBN|0-15-682750-6}}, p. 196
• German submarine {{SMU|UC-78||6}} was rammed and sunk in the English Channel off the coast of France by British steamer Queen Alexandra.{{cite Uboat.net|name=UC 78|id=UC+78 |type=1sub|accessdate=23 February 2009}}
• French ace René Fonck shot down six German aircraft in a day.{{cite web| date= August 1, 2001| url=http://acepilots.com/wwi/fr_fonck.html| title = René Fonck - Highest Scoring Allied Ace, 75 kills| publisher=acepilots.com| access-date=May 8, 2017| last=Sherman| first=Stephen}}
• Edgar Sisson, an American field operative for the Committee on Public Information posted in Petrograd, began to introduce the first in a series of 68 Russian documents together titled The German-Bolshevik Conspiracy that alleged Russian revolutionary leaders Vladimir Lenin and Leon Trotsky had worked with Germany to bring about Russia's withdraw from World War I.{{cite book| first=Alan| last=Axelrod| title=Selling the Great War: The Making of American Propaganda| url=https://archive.org/details/sellinggreatwarm00axel_0| url-access=registration| publisher=NY: Palgrave Macmillan| date=2009| page=[https://archive.org/details/sellinggreatwarm00axel_0/page/205 205]| isbn=9780230605039}} The documents were later proven to be forgeries.{{cite journal| first=George F.| last=Kennan| title=The Sisson Documents| journal=Journal of Modern History|volume=28| issue=2| date=1956| pages=130–54| doi=10.1086/237884| s2cid=144508744}}
• The Royal Air Force established air squadron No. 158.{{cite web|title=History of 158 Squadron| url=https://www.raf.mod.uk/history/158squadron.cfm| website=Royal Air Force| access-date=13 December 2017}}
• Born:
• Mike Wallace, American journalist, original and long-running member of the CBS news program 60 Minutes; as Myron Leon Wallace, in Brookline, Massachusetts, United States (d. 2012){{citation needed|date=March 2025}}
• Orville Freeman, American politician, 29th Governor of Minnesota, 16th United States Secretary of Agriculture; in Minneapolis, United States (d. 2003){{citation needed|date=March 2025}}
• Kyffin Williams, Welsh painter, best known for his landscape work of Wales; as John Kyffin Williams, in Llangefni, Wales (d. 2006){{citation needed|date=March 2025}}
• Died: Richard Hutton Davies, 56, English-New Zealand army officer, commander of the 6th Infantry Brigade and 20th Light Division during World War I, recipient of the Order of the Bath (b. 1861){{citation needed|date=March 2025}}

File:US Airmail inverted Jenny 24c 1918 issue.jpg U.S postage stamp, with the upside-down Curtiss Jenny airplane]]

• Battle of Kaniów – Around 8,000 troops with the Polish II Corps in Russia under command of Józef Haller were surprised and encircled by a larger Imperial German Army of 12,000 soldiers near Kaniów, Ukraine.{{in lang|pl}} Jacek Woyno, [http://archiwumcaw.wp.mil.pl/biuletyn/b25/b25_6.pdf MATERIAŁY ARCHIWALNE DO DZIEJÓW POLSKICH FORMACJI WOJSKOWYCH W ROSJI (1914—1920)] {{webarchive |url=https://web.archive.org/web/20141229192221/http://archiwumcaw.wp.mil.pl/biuletyn/b25/b25_6.pdf |date=December 29, 2014 }}, B I U L E T Y N Nr 25 WOJSKOWEJ SŁUŻBY ARCHIWALNEJ 2002
• German Zeppelin L 62 exploded and broke in half before crashing in flames over the North Sea with the loss of all hands. The German Naval Airship Service blamed her loss on an accident, while the Royal Air Force claimed one of its flying boats shot her down.Whitehouse, Arch, The Zeppelin Fighters, New York: Ace Books, 1966, no ISBN, pp. 239-240
• German submarine {{SMU|UB-16||6}} was torpedoed and sunk in the North Sea by Royal Navy submarine {{HMS|E34}} with the loss of 15 of her 16 crew.{{cite book| last=Messimer| first=Dwight R. |title=Verschollen: World War I U-boat losses| location= Annapolis, Maryland | publisher=Naval Institute Press| year=2002| isbn=978-1-55750-475-3| oclc=231973419| page=135}}
• The Inverted Jenny postage stamp, which features an upside-down image of a Curtiss Jenny airplane, was issued by the United States Postal Service by accident. While probably the most famous errors in American philately, only one pane in 100 was ever found showing the error, making it also one of the most prized with an estimated value of US $977,500.{{cite web |title=The 1918 24¢ Inverted "Jenny" |work=Sale 946a |publisher=Robert A. Siegel |date=2007-11-14 | url=http://www.siegelauctions.com/2007/946a/s946a.htm |access-date=2014-11-13}}
• Born:
• Peter Porekuu Dery, Ghanaian clergy, Archbishop of Tamale from 1974 to 1994; in Wa, Gold Coast (present-day Ghana) (d. 2008){{citation needed|date=March 2025}}
• R. N. Kao, Indian intelligence officer, first chief of the Research and Analysis Wing for the Government of India; as Rameshwar Nath Kao, in Benares, British India (present-day Varanasi, India) (d. 2002){{citation needed|date=March 2025}}
• T. Berry Brazelton, American pediatrician, developer of the Neonatal Behavioral Assessment Scale; as Thomas Berry Brazelton, in Waco, Texas, United States (d. 2018){{citation needed|date=March 2025}}
• George Welch, American air force officer and test pilot, recipient of the Distinguished Service Cross and Distinguished Flying Cross, Medal of Honor nominee for action during the attack on Pearl Harbor; in Wilmington, Delaware, United States (d. 1954, killed in a plane crash){{citation needed|date=March 2025}}
• Died: Alexander Oswald Brodie, 68, American army officer and politician, 15th Governor of the Arizona Territory, member of the Rough Riders during the Spanish–American War (b. 1849){{citation needed|date=March 2025}}

• The Mountainous Republic of the Northern Caucasus was officially established.{{Citation| last=Saparov| first=Arsène| year=2015| title=From Conflict to Autonomy in the Caucasus: The Soviet Union and the making of Abkhazia, South Ossetia and Nagorno Karabakh| publisher=Routledge| location=New York City| page=43}}
• Battle of Kaniów – After a full day of stiff resistance from the Polish II Corps in Russia, the German command offered a ceasefire. Germany suffered an estimated 1,500 dead while Polish forces sustained around 1,000 casualties, of those only two dozen died. Another 3,250 Polish troops were taken prisoner although many thousands, including commanding officer Józef Haller, managed to escape.{{in lang|pl}} Jacek Woyno, [http://archiwumcaw.wp.mil.pl/biuletyn/b25/b25_6.pdf MATERIAŁY ARCHIWALNE DO DZIEJÓW POLSKICH FORMACJI WOJSKOWYCH W ROSJI (1914—1920)] {{webarchive |url=https://web.archive.org/web/20141229192221/http://archiwumcaw.wp.mil.pl/biuletyn/b25/b25_6.pdf |date=December 29, 2014 }}, B I U L E T Y N Nr 25 WOJSKOWEJ SŁUŻBY ARCHIWALNEJ 2002
• Italian troopship {{SS|Verona|1908|2}} was sunk by German submarine {{SMU|UC-52||6}}, killing 880 passengers and crew.{{cite web |url=http://uboat.net/wwi/ships_hit/7357.html |title=Verona |publisher=Uboat.net |access-date=18 December 2012}}
• French Navy troopship Sant Anna was sunk in the Mediterranean Sea by German submarine {{SMU|UC-54||6}}, killing 605 passengers and crew.{{cite web |url=http://uboat.net/wwi/ships_hit/5425.html |title=Sant Anna |publisher=Uboat.net |access-date=20 December 2012}}
• German submarine {{SMU|U-154||6}} was torpedoed and sunk in the Atlantic Ocean by Royal Navy submarine {{HMS|E35}} with the loss of all 77 crew.{{cite Uboat.net|id=154|name=U 154|type=1sub|accessdate=22 January 2010}}
• Racing horse Exterminator with jockey Willie Knapp won the 44th running of the Kentucky Derby with a time of 2:10.08.{{Cite web |url=http://d3b4lt1s53xf6k.cloudfront.net/sites/kentuckyderby.com/files/charts/1918.pdf |title=1918 Kentucky Derby Results Tables |access-date=2018-04-09 |archive-url=https://web.archive.org/web/20110814060051/http://d3b4lt1s53xf6k.cloudfront.net/sites/kentuckyderby.com/files/charts/1918.pdf |archive-date=2011-08-14 |url-status=dead }}
• British artist Paul Nash opened his exhibition The Void of War at the Leicester Galleries in London.{{cite book|editor-first=Gordon |editor-last=Hughes |editor-first2=Philipp |editor-last2=Bloom |publisher=Getty Publishing |year=2014 |title=Nothing but the Clouds Unchanged:Artists in World War 1 |isbn=978-1-60606-431-3}}
• The sports Club Universitario de Buenos Aires was established in Buenos Aires. It is most noted for its rugby union team but also offered a wide range of sports disciplines including basketball, boxing, association football, gymnastics, golf, field hockey, martial arts, swimming, tennis, volleyball and many others.[http://www.cuba.org.ar/institucional/index.php History of CUBA on club's website]
• Born:
• Richard Feynman, American physicist, recipient of the Nobel Prize in Physics for his research into quantum mechanics; in New York City, United States (d. 1988){{citation needed|date=March 2025}}
• Sheila Burnford, Scottish-Canadian children's writer, author of The Incredible Journey; in Edinburgh, Scotland (d. 1984){{citation needed|date=March 2025}}
• Died: George Elmslie, 57, Australian politician, 25th Premier of Victoria (b. 1861){{citation needed|date=March 2025}}

• German submarine {{SMU|UB-72||6}} was depth charged and sunk in the English Channel by Royal Navy submarine {{HMS|D4}} with the loss of 34 of her crew.{{cite web |url=http://uboat.net/wwi/boats/index.html?boat=UB+72 |title=UB 72 |publisher=Uboat.net |access-date=12 November 2012}}
• German submarine {{SMU|U-103||6}} was rammed and sunk in the Atlantic Ocean by British ocean liner {{RMS|Olympic||2}} with the loss of nine of her 40 crew. Survivors were rescued by U.S. Navy destroyer {{USS|Davis|DD-65|6}}.{{cite book | last = McCartney | first = Innes |author2=Jak Mallmann-Showell |title=Lost Patrols: Submarine Wrecks of the English Channel | publisher = Periscope Publishing Ltd. | year = 2002 | isbn = 1-904381-04-9| page = 36}}{{cite book | last = Kemp | first = Paul| title=U-Boats Destroyed (German submarine losses in the World Wars)| publisher = Arms and Armour Press | year = 1997 | location = London | isbn = 1-85409-321-5| page = 49}}
• The football Sport Club Gaúcho was established in Passo Fundo, Brazil.{{cite book|title=Escudos dos Times do Mundo Inteiro|publisher=Panda Books|author=Rodolfo Rodrigues|year=2009|page=77}}
• Born:
• Julius Rosenberg, American spy, convicted along with Ethel for sharing state secrets with the Soviet Union; in New York City, United States (d. 1953, executed){{citation needed|date=March 2025}}
• Mary Kay Ash, American business executive, founder of Mary Kay Cosmetics; as Mary Kathlyn Wagner, in Hot Wells, Texas, United States (d. 2001){{citation needed|date=March 2025}}
• Died: Rose Selfridge, 57, American-British socialite, wife to Harry Gordon Selfridge, the owner of the Selfridges department store chain (b. 1860){{citation needed|date=March 2025}}

• The United States Postal Service issued the first airmail stamps to the public, bearing a picture of a Curtis "Jenny" airplane.Anonymous, "Today in History," The Washington Post Express, May 13, 2013, p. 26
• German submarine {{SMU|UB-114||6}} sank at Kiel, Germany with the loss of seven of her crew. The vessel was later raised.{{cite web |url=http://uboat.net/wwi/boats/index.html?boat=UB+114 |title=UB 114 |publisher=Uboat.net |access-date=15 November 2012}}
• The French Army established the 501st Combat Tank Regiment.Avec les chars d'assaut Marcel Fourier. Hachette, 1919 (Témoins), pp. 308-310)
• Children's author L. Frank Baum published the 12th Oz book, The Tin Woodman of Oz, which helped reverse a trend in declining book sales of the series.Katharine M. Rogers, L. Frank Baum: Creator of Oz, New York, St. Martin's Press, 2002; pp. 230-1.
• Filmmaker William Desmond Taylor released Huck and Tom as a sequel to Tom Sawyer, with Jack Pickford and Robert Gordon reprising their roles of the Mark Twain characters.[http://www.silentera.com/PSFL/data/H/HuckAndTom1918.html Progressive Silent Film List: Huck and Tom] at silentera.com[http://www.afi.com/members/catalog/DetailView.aspx?s=&Movie=2327 The AFI Catalog of Feature Films: Huck and Tom]
• Fatty Arbuckle starred in the comedy short Moonshine, which he also directed. Portions of the film still survive.{{cite web |url=http://www.silentera.com/PSFL/data/M/Moonshine1918.html |title=Progressive Silent Film List: Moonshine |access-date=February 26, 2008|work=silentera.com}}
• Born: Balasaraswati, Indian dancer and choreographer, known for her promotion of Bharatanatyam traditional dance, recipient of the Padma Bhushan and Padma Vibhushan civilian awards in India; as Tanjore Balasaraswati, in Madras, British India (present-day Chennai, India) (d. 1984){{citation needed|date=March 2025}}

• Royal Navy destroyer {{HMS|Phoenix|1911|6}} was torpedoed and sunk in the Adriatic Sea by Austro-Hungarian submarine {{SMU|U-27|Austria-Hungary|6}}, killing two of the 72 crew.{{cite book | last = Gibson | first = R. H. |author2=Maurice Prendergast | title = The German Submarine War, 1914–1918 | location = Annapolis, Maryland | publisher = Naval Institute Press | year = 2003 | orig-year = 1931 | isbn = 978-1-59114-314-7 | oclc = 52924732|page=271 }}{{cite web|url=http://www.naval-history.net/xDKCas1918-05May.htm|title=Royal Naval Casualties May 1918 at Naval-History.net|access-date=2008-09-28}}
• South African mayor Harry Hands instituted the "Three Minute Pause", which was initiated by the daily firing of the Noon Gun on Signal Hill in Cape Town, South Africa. The ceremony inspired the introduction of the two-minute silence in November 1919.Royal Canadian Legion Branch # 138.[http://people.becon.org/~rcl138/milestone.php "2-Minute Wave of Silence" Revives a Time-honoured Tradition]. Accessed on 5 June 2014.
• Iowa Governor William L. Harding issued a hard-line anti-German proclamation (later known as the Babel Proclamation) that stated "only English was legal in public or private schools, in public conversations, on trains, over the telephone, at all meetings, and in all religious services."Derr, Nancy. "The Babel Proclamation," The Palimpsest 60, No. 4 (July/August 1979): pp. 100-101
• Born: James Hardy, American surgeon, performed the first lung transplant; in Newala, Alabama, United States (d. 2003){{citation needed|date=March 2025}}
• Died: James Gordon Bennett Jr., 77, American newspaper mogul, publisher of the New York Herald (b. 1841){{citation needed|date=March 2025}}

• The White Guards captured Russian-held Fort Ino at Neva Bay, Finland, formally ending all fighting in the Finnish Civil War.Keränen et al. 1992, pp. 123–137
• The United States Postal Service started the world's third regular airmail service between New York City, Philadelphia and Washington, D.C. Postmaster General Albert S. Burleson assigned Assistant Post Master General Otto Praeger additional duties as the first chief of the United States airmail service, telling Praeger, "The airmail once started must not stop, but must be constantly improved and expanded until it would become, like the steamship and the railroad, a permanent transportation feature of the postal service."Jensen, Richard, "The Suicide Club," Aviation History, May 2017, p. 62.{{cite encyclopedia|title=Who's who in American Aeronautics| url=https://books.google.com/books?id=VRpaAAAAYAAJ&q=Otto+Praeger+died&pg=PA85|year=1922 |access-date=2017-04-02 }}
• The Royal Air Force established air squadron No. 145.{{cite web| title=History of 145 Squadron| url=https://www.raf.mod.uk/history/145squadron.cfm| website=Royal Air Force| access-date=13 December 2017| archive-url=https://web.archive.org/web/20170703184657/https://www.raf.mod.uk/history/145squadron.cfm| archive-date=3 July 2017| url-status=dead}}
• The Packard-Le Père aircraft was first flown.Angelucci, Enzo, The American Fighter: The Definitive Guide to American Fighter Aircraft From 1917 to the Present, New York: Orion Books, 1987, p. 195
• Construction began on the Brooklyn Army Terminal in New York City and would open in September 1919, ten months after World War I ended.{{cite news|url=http://bklyn.newspapers.com/image/55629106/?terms=%27brooklyn%2Barmy%2Bbase%22|title=Uncle Sam Pay Roll $200,000 A Week at Bay Ridge War Base|date=August 25, 1918|work=Brooklyn Daily Eagle|access-date=August 20, 2018|page=15|via=Brooklyn Public Library; newspapers.com}} {{open access}}
• Osaka Nomura Bank, as predecessor of Resona Holdings, a major financial group in Japan, was founded.:ja:大阪野村銀行#沿革 (Japanese language edition) Retrieved on May 27, 2020.
• The football club Violette was established in Port-au-Prince, Haiti.[http://www.haiti-reference.com/loisirs/football/equipes.php Haiti Reference: Le Football Haitien: Équipes et Clubs]
• Born:
• Eddy Arnold, American country music singer, second best-selling country music artist of all time with over 85 million records; as Richard Edward Arnold, in Henderson, Tennessee, United States (d. 2008){{citation needed|date=March 2025}}
• Joseph Wiseman, Canadian actor, best known for Dr. No in the first James Bond film; in Montreal, Canada (d. 2009){{citation needed|date=March 2025}}
• Arthur Jackson, American sharpshooter, bronze medalist at the 1952 Summer Olympics; in New York City, United States (d. 2015){{citation needed|date=March 2025}}

File:Kenraali C. G. E. Mannerheim (26936604946).jpg in uniform with an armband showing the coat of arms of Finland|alt=A studio-style picture of General Mannerheim, commander-in-chief of the White Army. He is looking away with his left shoulder turned towards the camera. On his left arm, a white armband shows the coat of arms of Finland.]]

• United States Congress approved the Sedition Act, which extended the Espionage Act to cover a broader range of offenses including public speech or expression that cast the U.S. Government or its war effort in a negative light or interfered with its sale of war bonds.Kennedy, David M., Over Here: The First World War and American Society (NY: Oxford University Press, 2004), p. 80Stone, Geoffrey R., Perilous Times: Free Speech in Wartime from the Sedition Act of 1798 to the War on Terrorism (NY: W. W. Norton & Company, 2004), p. 541
• White Guard commander Carl Gustaf Emil Mannerheim held a victory parade in Helsinki to formally celebrate the end of the Finnish Civil War.Keränen et al. 1992, pp. 123–137
• The Imperial German Navy recommissioned the light cruiser Stuttgart as a seaplane tender, the only German seagoing aviation ship capable of working with the fleet commissioned during both world wars.Layman, R.D., Before the Aircraft Carrier: The Development of Aviation Vessels 1849-1922, Annapolis, Maryland: Naval Institute Press, 1989, {{ISBN|0-87021-210-9}}, p. 27
• The United States Army established the Third Corps to support Allied forces on the Western Front.{{cite book|first=John B. |last=Wilson |title=Armies, Corps, Divisions, and Separate Brigades |year=1999 |publisher=United States Army Center of Military History |isbn= 978-0160499920| chapter = III Corps | page=53| chapter-url = http://www.history.army.mil/BOOKS/Lineage/ACDSB/ACDSB-FM.htm}}
• The Ukrainian Socialist-Revolutionary Party split into two factions during its fourth congress.[http://history.franko.lviv.ua/IIIu_3.htm Ukrainian Party of Socialist Revolutionaries]. Handbook on the History of Ukraine
• Ukrinform was established as the national news agency for Ukraine, with nationalist leader Dmytro Dontsov as its first director.[http://www.nrcu.gov.ua/index.php?id=148&listid=66334 Ukrainian National News Agency UKRINFORM celebrates its 90th anniversary], National Radio Company of Ukraine (May 15, 2008)[http://www.kmu.gov.ua/control/en/publish/article?art_id=13256968&cat_id=32740 On March 1 the national news agency Ukrinform launched Ukraine's first Internet radio service], Government of Ukraine (March 2, 2005)
• Hazel Turner, a black farmer, was lynched by a white mob in Lowndes County, Georgia on suspicion for the shooting death of local farmer Hampton Smith, based on the assumption it was because of a public dispute between the two men. Turner's death was one of 13 black men killed by a vigilante mob on behalf of the Smith family.{{Cite news| volume = 16| issue = 5| pages = 221–223| last = White| first = Walter F| author-link = Walter Francis White| title = The work of a mob| work = The Crisis| date = September 1918| url = https://books.google.com/books?id=ZVoEAAAAMBAJ&pg=PA221}}
• The Shenandoah National Forest was established in the Appalachian Mountains of the United States. It was renamed George Washington National Forest in 1932, with the Jefferson National Forest added to the preserve in 1936.{{cite web| url=http://www.foresthistory.org/ASPNET/places/National%20Forests%20of%20the%20U.S.pdf| title=The National Forests of the United States |publisher=The Forest History Society| last=Davis| first=Richard C.|date=2005-09-29| access-date=2009-01-18 |archive-url=https://web.archive.org/web/20090205110527/http://www.foresthistory.org/Research/usfscoll/places/National%20Forests%20of%20the%20U.S.pdf |archive-date=2009-02-05 |url-status=dead}}
• Born: Wilf Mannion, English football player, inside forward for Middlesbrough from 1936 to 1954, and the England national football team from 1946 to 1951; as Wilfrid James Mannion, in South Bank, North Yorkshire, England (d. 2000){{citation needed|date=March 2025}}
• Died: Eusapia Palladino, 64, Italian spiritualist, best known for her séance demonstrations (b. 1854){{citation needed|date=March 2025}}

• German submarine {{SMU|UC-35||6}} was shelled and sunk in the Mediterranean Sea by a French Navy patrol ship with the loss of 20 of her 25 crew.{{cite web |url=http://uboat.net/wwi/boats/index.html?boat=UC+35 |title=UC 35 |publisher=Uboat.net |access-date=26 September 2012}}
• The fraternity Pi Kappa Lambda was established at Northwestern University in Evanston, Illinois and became known as a music education fraternity.[http://www.pikappalambda.org/ Official website]
• Japanese industrial paint manufacturer Kansai Paint was established in Amagasaki, Japan.{{cite web|title=Kansai -Corporate Profile|url=http://www.kansai.com/about-us/|website=Kansai.com|access-date=26 November 2017}}
• The sports Club Atlético Banco de la Provincia de Buenos Aires was established in Vicente López, Argentina. It now has sections in field hockey, basketball, association football, gymnastics, golf, swimming, tennis, and martial arts.[http://www.clubbpba.com.ar/principa.htm Historia del Club at official site]
• Born:
• Birgit Nilsson, Swedish opera singer, best known for performances in Wagner operas for various companies including the Royal Swedish Opera; as Märta Birgit Nilsson, in Västra Karup, Sweden (d. 2005){{citation needed|date=March 2025}}
• Robert Shields, American minister and teacher who became known for writing a diary of 37.5 million words, possibly the longest ever written; in Seymour, Indiana, United States (d. 2007){{citation needed|date=March 2025}}
• Died: William Drew Robeson, 73, American religious leader, minister of the black branch of the First Presbyterian Church of Princeton, father of singer and actor Paul Robeson (b. 1844){{citation needed|date=March 2025}}

• French Navy destroyer {{ship|French destroyer|Catapulte||2}} collided with British cargo ship and sank in the Mediterranean Sea off Algeria.{{cite web|url=http://www.naval-history.net/WW1NavyFrench.htm |title=French Navy |publisher=Naval History |access-date=21 February 2013}}
• Royal Navy cargo ship SS Chesterfield, was torpedoed and sunk in the Mediterranean Sea by German submarine {{SMU|UC-52||6}} with the loss of four of her crew.{{cite web |url=http://uboat.net/wwi/ships_hit/1244.html |title=Chesterfield | publisher=Uboat.net |access-date=18 December 2012}}
• The British Indian Army established the 11th Gurkha Rifles for the Mesopotamian campaign.{{cite book| last=Perry| first=F.W| year=1993| title=Order of Battle of Divisions Part 5B. Indian Army Divisions| publisher=Ray Westlake Military Books| location= Newport| isbn=1-871167-23-X| page=80}}
• The football league Federação Gaúcha de Futebol was established to manage all football tournaments in Rio Grande do Sul, Brazil.{{cite book| title=Escudos dos Times do Mundo Inteiro| publisher=Panda Books| author=Rodolfo Rodrigues| year=2009| page=36}}
• The football club Ølstykke was established in Ølstykke, Denmark.{{cite web|title=The formation of Idrætsforening 1918| url=http://live-1322-oelstykke-fc.umbraco-proxy.com/oelstykke-kroenikken/de-foerste-aar/stiftelsen/| website=Ølstykke F.C.| access-date=4 December 2017| language=da}}
• Born: Tom Bolack, American politician, 20th Governor of New Mexico; as Thomas Felix Bolack, in Cowley County, Kansas, United States (d. 1998){{citation needed|date=March 2025}}
• Died: Toivo Kuula, 34, Finnish composer, known for works including Stabat mater and Ostrobothnian Suites (b. 1883){{citation needed|date=March 2025}}

File:Gervais Raoul Lufbery (LC-USZ62-101970).jpg Raoul Lufbery]]

• French flying ace Raoul Lufbery was killed when he fell from his plane during a dogfight with a German aircraft. He had 17 confirmed victories at the time of his death.Rickenbacker, Edward V. (1919). Fighting the Flying Circus. New York: Frederick A. Stokes Company; pp. 94-96
• Mary Turner, wife to Hazel Turner who was also pregnant, was lynched and burned to death by a white mob in Lowndes County, Georgia after speaking out against her husband's lynching three days earlier.{{cite web | url=http://www.maryturner.org/images/place.pdf | title=A Place to Lay Their Heads | access-date=November 23, 2015 | author=Forehand, C. Tyrone}}{{Cite news|last = Ramos|first = Kara |title = Remembering a dark page of history|work = Valdosta Daily Times|location = Valdosta, GA|access-date = 2013-05-23|date = 2010-05-15|url = http://valdostadailytimes.com/local/x712209351/Remembering-a-dark-page-of-history}} Despite a state investigation that identified 15 suspects involved in the lynching, no charges were laid.{{cite book| first=Patricia|last=Bernstein|title=The First Waco Horror| year=2005|place=College Station|publisher=Texas A&M University Press| page=176}}
• U.S. Army Major Harold M. Clark Jr. and Sergeant Robert P. Gay make the first inter-island flight in Hawaii, flying from Fort Kamehameha on Oahu to Maui. They continued on to the island of Hawaii the same day, where they crashed on the slopes of Mauna Kea. Uninjured, they wandered on foot for a week before finding help.[http://hawaii.gov/hawaiiaviation/chronology-of-aviation-in-hawaii/1879-1919/ Aviation Hawaii: 1879-1919 Chronology of Aviation in Hawaii]
• The film drama Old Wives for New, directed by Cecil B. DeMille, was released to controversy with its depiction of star Elliott Dexter actively seeking an adulterous affair. Despite the illicit material, the film became the fifth-highest grossing of the year. Copies of the film survive at the George Eastman Museum in Rochester, New York.{{cite web | url=http://www.silentera.com/PSFL/data/O/OldWivesForNew1918.html |title=Progressive Silent Film List: Old Wives for New |access-date=2008-04-17|work=silentera.com}}
• Born:
• Abraham Pais, Dutch-American physicist, known for collaborations with Niels Bohr and Albert Einstein; in Amsterdam, Netherlands (d. 2000){{citation needed|date=March 2025}}
• Edward Blyden, Sierra Leone diplomat, ambassador to the United Nations, grandson of Edward Wilmot Blyden; in Freetown, Protectorate of Sierra Leone (present-day Sierra Leone) (d. 2010){{citation needed|date=March 2025}}
• Died:
• Ferdinand Hodler, 65, Swiss painter, member of the Symbolism movement with works including Night (b. 1853){{citation needed|date=March 2025}}
• George Bent, 75, Native American soldier, member of the Cheyenne nation who fought with the Confederates during the American Civil War, known for his collaborations with anthropologist George Bird Grinnell (b. 1843){{citation needed|date=March 2025}}

• Germany launched the largest, and last, heavier-than-air raid against the United Kingdom of World War I, with 38 Gotha and three Riesenfkugzeug bombers participating. The bombers dropped 2,724 pounds (1,236 kg) of bombs according to British estimates or 1,500 kilograms (3,307 pounds) according to the Germans, killing 49 people, injuring 177, and inflicting £117,317 in damage. British fighters and antiaircraft guns shot down six Gothas, and a seventh was forced to land in England. Germany had made a total 27 heavier-than-air raids, dropping 111,935 kg (246,774 lbs) of bombs that killed total 835 people, injured 1,972, and inflicted £1,418,272 of damages in exchange for the loss of 62 bombers either shot down or crashed while returning to base.Fredette, Raymond H., The Sky on Fire: The First Battle of Britain 1917–1918, New York: Harvest, 1976, {{ISBN|0-15-682750-6}}, p. 266
• The small town of Codell, Kansas was hit for the third year in a row on the same date by a tornado, killing 10 people and damaging the town's school, Methodist church, hotel and several residencies. The third tornado proved to be the most damaging to the town's economy and it did not fully recover after the disaster."Tornado Traverses Trego, Ellis, Rooks and Osborne Counties. Ten Killed, Scores of Injured. Property Damage in Million. Codell in Part Ruins.", Plainville Times, 23 May 1918, p. 1
• A special anti-conscription convention was held in Dublin, where leaders condemned the arrest and deportation of Sinn Féin leaders Éamon de Valera and Arthur Griffith for their alleged involvement in the "German Plot".{{cite web | url=http://www.waterfordmuseum.ie/exhibit/web/Display/article/283/3/The_Hay_Plan__Conscription_In_Ireland_During_WW1_Nationalist__Union_Opinions.html |title=The Hay Plan & Conscription in Ireland During WW1 |last1=Hennessy |first1=Dave |publisher=Waterford County Museum |access-date=11 December 2012}}
• The United States Army Aviation Section separated from Signal Corps and was divided into the Division of Military Aeronautics and the Bureau of Aircraft Production.Craven, Wesley Frank, and Cate, James Lea, editors (1983). The Army Air Forces In World War II, Air Force Historical Studies Office, {{ISBN|0-912799-03-X}} (Vol. 1), p. 9
• Born:
• Edward B. Lewis, American geneticist, recipient of the Nobel Prize in Physiology or Medicine for the development of evolutionary developmental biology; in Wilkes-Barre, Pennsylvania, United States (d. 2004){{citation needed|date=March 2025}}
• David Ormsby-Gore, British diplomat, 36th Ambassador of the United Kingdom to the United States; as William David Ormsby-Gore, in London, England (d. 1985){{citation needed|date=March 2025}}
• Piru Singh, Indian army officer, member of the Rajputana Rifles during the Indo-Pakistani War, recipient of the Param Vir Chakra; as Piru Singh Shekhawat, in Beri, British India (present-day India) (d. 1948, killed in action){{citation needed|date=March 2025}}

• Battle of Sardarabad – An Ottoman army of 13,000 soldiers invaded Armenia by taking Sardarabad and advancing on the city of Yerevan.{{in lang|tr}} Gürbüz, Mustafa, [http://www.eraren.org/index.php?Lisan=tr&Page=DergiIcerik&IcerikNo=498 "1917 Rus İhtilali Sonrası Kafkasya'da Türk Askeri Faaliyetleri: Serdarabad Savaşları ve Siyasi Sonuçları"] [Turkish Military Operations in the Caucasus after the 1917 Russian Revolution: The battles of Serdarabad and its Political Results]. Ermeni Araştırmaları, No. 25, 2007
• U.S. Navy patrol ship {{USS|Christabel|SP-162|6}} damaged German submarine SM UC-56 when it attempted to attack a British merchant ship it was escorting in the Atlantic Ocean off the coast of Spain.{{cite web | last = Helgason | first = Guðmundur | title = WWI U-boats: UC-56| url = http://uboat.net/wwi/boats/index.html?boat=UC+56 | work = U-Boat War in World War I | publisher = Uboat.net | access-date = 29 September 2012 }}
• A fire destroyed an airplane manufacturing plant owned by Fowler Airplane Corporation in San Francisco, destroying 15 aircraft models and costing somewhere between $250,000 and $1 million in damages.Wire service, "Fifteen Air Planes Are Destroyed By Big Fire", Daily News, Red Bluff, California, Wednesday 22 May 1918, Volume XXXIV, Number 169, page 1.{{cite web| url=http://www.dommagazine.com/article/factory-fires-and-other-challenges-aircraft-builder| title=Factory Fires and Other Challenges of Aircraft Builder DOM Magazine| work=dommagazine.com| access-date=13 October 2016}}
• Born:
• Lloyd Hartman Elliott, American academic, president of George Washington University from 1965 to 1988; in Clay County, West Virginia, United States (d. 2013){{citation needed|date=March 2025}}
• Robin McNair, British air force officer, commander of the No. 247, No. 74 Squadrons and No. 124 Wing during World War II, recipient of the Distinguished Flying Cross; in Rio de Janeiro, Brazil (d. 1996){{citation needed|date=March 2025}}
• Karl Schwanzer, Austrian architect, designer of the 21er Haus and BMW Headquarters buildings; in Vienna, Austria-Hungary (present-day Austria) (d. 1975){{citation needed|date=March 2025}}

• Battle of Sardarabad – The Armenian Army Corps of 9,000 men managed to force the Ottomans back to regroup at the Araks River.{{in lang|hy}} Harutunyan, Ashot H. «Սարդարապատի ճակատամարտ 1918» [The Battle of Sardarapat, 1918]. Armenian Soviet Encyclopedia. Yerevan: Armenian Academy of Sciences, 1984, vol. x, pp. 227-228.
• Battle of Abaran – An Armenian force of 1,000 riflemen halted the Ottoman advance towards Hamamlu at the Bash Abaran in Armenia.Yalçın Murgul, "Baku Expedition of 1917–1918: A Study of the Ottoman Policy towards the Caucasus", Master's Thesis, 2007, Department of History Bilkent University, [http://www.thesis.bilkent.edu.tr/0003428.pdf p. 55.]
• Axeman of New Orleans – Joseph Maggio, an Italian grocer in New Orleans, and his wife Catherine were murdered in their own home while sleeping. The killer cut both of their throats with a razor and bludgeoned them with an axe. Joseph survived long enough to be found by his brothers to report the attack. It set off a string of similar murders that terrorized the city until 1919 when the murder spree stopped. None of the serial murders have been solved.{{cite book|first=Cameron|last=Gibson|title=Serial Murder and Media Circuses|publisher=Greenwood Publishing|location=Westport, CT|isbn= 0275990648|year=2006|page=18}}
• The Handley Page aircraft was first flown.Bowyer, Chaz. Handley Page Bombers of the First World War. Bourne End, Bucks, UK:Aston Publications, 1992. {{ISBN|0-946627-68-1}}. pp. 122-123
• Born:
• Lude Check, Canadian ice hockey player, left winger for the Detroit Red Wings and Chicago Blackhawks from 1943 to 1951; as Ludic Albert Check, in Brandon, Manitoba, Canada (d. 2009){{citation needed|date=March 2025}}
• John C. Haas, American business executive, chairman of Rohm and Haas from 1974 to 1978; in Haverford, Pennsylvania, United States (d. 2011){{citation needed|date=March 2025}}

• Costa Rica declared war on Germany.{{cite web |url=https://www.loc.gov/law/help/digitized-books/world-war-i-declarations/foreign.php#U |title=World War: Declarations of War from Around the World|publisher=Library of Congress}}{{cite web |url=http://www.firstworldwar.com/features/declarationsofwar.htm |title=Who Declared War and When|publisher = Firstworldwar.com}}
• Royal Navy troopship {{RMS|Moldavia}} was torpedoed and sunk in the English Channel by German submarine {{SMU|UB-57||6}} with the loss of 56 lives.{{cite web| title = SS Moldavia| publisher = Shipping Times| url = http://www.clydesite.co.uk/clydebuilt/viewship.asp?id=15332| archive-url = https://web.archive.org/web/20040907045459/http://www.clydesite.co.uk/clydebuilt/viewship.asp?id=15332| url-status = usurped| archive-date = 7 September 2004| access-date =20 July 2009 }}
• German submarine {{SMU|UB-52||6}} was torpedoed and sunk in the Strait of Otranto by Royal Navy submarine {{HMS|H4}} with all hands lost.{{cite web |url=http://uboat.net/wwi/boats/index.html?boat=UB+52 |title=UB 52 |publisher=Uboat.net |access-date=10 November 2012}}
• British passenger ship Innisfallen was torpedoed and sunk in the Irish Sea by German submarine {{SMU|UB-64||6}} with the loss of 10 lives.{{cite web |url=http://uboat.net/wwi/ships_hit/3026.html |title=Innisfallen |publisher=Uboat.net |access-date=11 November 2012}}
• The U.S. government approved the temporary assignment of U.S. air service cadets undergoing training to the Royal Italian Army's Military Aviation Corps so they could complete their tactical training with assignments to Italian bomber squadrons during combat operations, and with the right to transfer them to American units at any time.Blumberg, Arnold, "Bombing, Italian Style," Aviation History, November 2015, p. 50
• The Ukrainian Navy established its own infantry.{{Cite web |url=http://fleet.sebastopol.ua/morskaderzhava/index.php?article_to_view=18 |title=Морська Держава :: Головна сторiнка - Анонси |access-date=2018-04-09 |archive-url=https://web.archive.org/web/20070927035630/http://fleet.sebastopol.ua/morskaderzhava/index.php?article_to_view=18 |archive-date=2007-09-27 |url-status=dead }}
• Born:
• Frank Mancuso, American major league baseball player and politician, catcher for the St. Louis Browns and Washington Senators from 1944 to 1947, member of Houston City Council from 1963 to 1994; in Houston, United States (d. 2007){{citation needed|date=March 2025}}
• Walter Jackson Bate, American literary critic, recipient of the Pulitzer Prize for the biographies of John Keats in 1964 and Samuel Johnson in 1978; in Mankato, Minnesota, United States (d. 1999){{citation needed|date=March 2025}}
• Denis Compton, English cricketer, batsman and bowler for Middlesex from 1936 to 1958, the Marylebone Cricket Club from 1936 to 1964 and the England cricket team from 1937 to 1957; in Hendon, England (d. 1997){{citation needed|date=March 2025}}
• Died:
• Mariano Ponce, 55, Filipino politician, one of the founders of the news organization La Solidaridad (b. 1863){{citation needed|date=March 2025}}
• Gerard Noel, 73, British naval officer, leading naval commander in the Second Anglo-Ashanti War, recipient of the Order of the Bath and Order of St Michael and St George (b. 1845){{citation needed|date=March 2025}}

• Battle of Sardarabad – The Armenian Army Corps failed in their attempts to dislodge the Ottomans from their defensive positions around Araks River.Harutunyan 1984, pp. 227-228
• Canadian women obtained the right to vote in federal elections. However, women identified as Status Indian were not given voting rights until 1960.Canadian Research Institute for the Advancement of Women. http://criaw-icref.ca/millenium {{Webarchive|url=https://web.archive.org/web/20140102194633/http://criaw-icref.ca/millenium |date=2014-01-02 }}
• U.S. President Woodrow Wilson issued an executive order to establish the United States Army Air Service to replace the Aviation Section of the U.S. Signal Corps. The Bureau of Aircraft Production and the Division of Military Aeronautics was also established to develop military aircraft the new air force.{{cite book |last=Greer |first= Thomas H. |year=1985 |title=USAF Historical Study 89, The Development of Air Doctrine in the Army Air Arm, 1917–1941 |publisher=Center For Air Force History |location=Maxwell Air Force Base|url=http://www.afhra.af.mil/shared/media/document/AFD-090601-130.pdf |archive-url=https://web.archive.org/web/20120120073113/http://www.afhra.af.mil/shared/media/document/AFD-090601-130.pdf |url-status=dead |archive-date=January 20, 2012 |access-date=10 Nov 2010 }}, p. 149, Appendix 2 Redesignations of the Army Air Arm, 1907–1942.Maurer, pp. 3-4
• The Red Air Fleet was established, the predecessor of the Soviet Air Forces.Hardesty, Von, Red Phoenix: The Rise of Soviet Air Power 1941-1945, Washington, D.C.: Smithsonian Institution Press, 1982, {{ISBN|0-87474-510-1}}, p. 36
• József Kiss, Austria-Hungary's fifth-highest-scoring ace, was shot down and killed in combat. He had scored 19 victories.{{cite web|last1=Duffy|first1=Michael|title=Who's Who-Josef Kiss| url=http://www.firstworldwar.com/bio/kiss.htm| website=First World War.com| access-date=9 April 2018}}
• The Confederación Sudamericana de Atletismo was established as the governing body for athletics in South America.{{Citation | last = Confederación Sudamericana de Atletismo | title = Historial – El origen de la ConSudAtle | url = http://www.consudatle.org/historial.php | language = es | access-date = July 19, 2011 | url-status = usurped | archive-url = https://web.archive.org/web/20110621040345/http://www.consudatle.org/historial.php | archive-date = June 21, 2011 }}
• Composer Béla Bartók premiered his opera Bluebeard's Castle at the Royal Hungarian Opera House in Budapest.[http://www.bartokrecords.com/articles/bluebeards-castle/ Peter Bartók. Bluebeard's Castle - English translation. Bartók Records. August, 2008]
• The football club Piteå was established in Piteå, Sweden. Its women's division plays in Damallsvenskan, the highest women's association football league in Sweden, while the men's plays in Division 2.{{cite web| title=About the club| url=https://www.piteaif.se/piteaif/om| website=Piteå IF| access-date=4 December 2017}}
• Born:
• Peter J. Brennan, American public servant, 13th United States Secretary of Labor; in New York City, United States (d. 1996){{citation needed|date=March 2025}}
• Jack Wrather, American business executive and television producer, known for classic 1950s television shows including The Lone Ranger, Sergeant Preston of the Yukon, and Lassie; as John Devereaux Wrather Jr., in Amarillo, Texas, United States (d. 1984){{citation needed|date=March 2025}}
• Coleman Young, American politician, 66th Mayor of Detroit, first African American mayor of Detroit; in Tuscaloosa, Alabama, United States (d. 1997){{citation needed|date=March 2025}}

• Battle of Karakilisa – An Ottoman force of 10,000 soldiers marched on Karakilisa, Armenia where it met an Armenian force of 6,000 militia.{{cite book | last = Walker | first = Christopher | title = ARMENIA: The Survival of a Nation | publisher = St. Martin's Press | date = 1980 | location = New York | isbn = 0-7099-0210-7 | page = [https://archive.org/details/armeniasurvivalo0000walk/page/254 254] | url = https://archive.org/details/armeniasurvivalo0000walk/page/254 }}
• Battle of Abaran – After three days of fierce fighting, the Armenians counterattacked Ottoman forces at the Bash Abaran in Armenia.Murgul 2007, p. 55
• The Ministry of Foreign Affairs was established for the Democratic Republic of Georgia.{{cite web |url=http://wwhp.ru/gruzi-mid.htm |title=МИНИСТРЫ ИНОСТРАННЫХ ДЕЛ ГРУЗИИ |trans-title=Ministers of Foreign Affairs of Georgia |access-date=2011-02-17 |archive-url=https://web.archive.org/web/20101227071738/http://wwhp.ru/gruzi-mid.htm |archive-date=2010-12-27 |url-status=dead }}
• The Czechoslovak Communist Party was established in Moscow as a sort of government in exile until the Czechoslovak region gained independence from the Central Powers.{{cite web |url=http://www.osaarchivum.org/files/holdings/300/8/3/text/15-1-44.shtml |title=Archived copy |access-date=2008-11-23 |url-status=dead |archive-url=https://web.archive.org/web/20110717200248/http://www.osaarchivum.org/files/holdings/300/8/3/text/15-1-44.shtml |archive-date=2011-07-17 }}Institute of Marxism–Leninism of the CPCz CC, Institute of Marxism–Leninism of the CPS CC. An Outline of the History of the CPCz. Prague: Orbis Press Agency, 1980. p. 75
• James Joyce's Exiles: a play in three acts was published in London.{{Cite journal| last=MacNicholas| first=John| date=1981-01-01| title=The Stage History of "Exiles"| jstor=25476401|journal=James Joyce Quarterly| volume=19| issue=1| pages=9–26}}
• Born: Fredrik Kayser, Norwegian army officer, member of the Norwegian Independent Company 1 during World War II, recipient of the St. Olav's Medal with Oak Branch, Military Medal and Legion of Honour (d. 2009){{citation needed|date=March 2025}}
• Died: William Pitt, 62, Australian architect, designer of major landmarks in Melbourne including the Queens Bridge (b. 1855){{citation needed|date=March 2025}}

• The Transcaucasian Democratic Federative Republic was abolished, allowing Georgia to declare its independence.{{Citation|last=Suny|first=Ronald Grigor|author-link=Ronald Grigor Suny|year=1994|title=The Making of the Georgian Nation|edition=Second|publisher=Indiana University Press|location=Bloomington, Indiana|isbn=978-0-25-320915-3|pages=191–192}}
• German submarine {{SMU|UB-74||6}} was depth charged and sunk in Lyme Bay by a Royal Navy ship, killing all 35 crew.{{cite web |url=http://uboat.net/wwi/boats/index.html?boat=UB+74 |title=UB 74 |publisher=Uboat.net |access-date=12 November 2012}}
• The British built Kyarra was torpedoed and sunk one mile off Anvil Point, near Swanage, England by a UB-57 German submarine, killing 6 crew.{{cite web |url=http://www.sskyarra.com/ |title=SS Kyarra |work=sskyarra.com |year=2009 |access-date=4 September 2012 |url-status=dead |archive-url=https://web.archive.org/web/20120306085458/http://www.sskyarra.com/ |archive-date=6 March 2012 |df=dmy-all }}

• German spring offensive – German forces launched the third stage of their offensive against the Allies on the Western Front with Operation Blücher-Yorck, beginning with the attack on Aisne River in France. Taking advantage of thinly spread out defenses, the Germans advanced through a 40 km (25 mi) gap in the Allied line, punched through eight Allied divisions between Reims and Soissons, and gained another 15 km to the Vesle River by nightfall.Hart, Peter (2008). 1918: A Very British Victory, Phoenix Books, London. {{ISBN|978-0-7538-2689-8}}, pp. 266-268, 283
• Battle of Sardarabad – An Armenian force attacked the Ottoman Army from the rear while the main group pounded its front defenses, inflicting 3,500 casualties and forcing the Ottoman command to order a retreat.Harutunyan 1984, pp. 227-228
• The Azerbaijani National Council was established as the governing body of Azerbaijan Democratic Republic.Protocols of Muslim Faction of Transcaucasian Seym and Azerbaijan National Council. 1918. Baku, Adiloglu, 2006 (in Azeri and Russian)
• Born:
• Yasuhiro Nakasone, Japanese state leader, 45th Prime Minister of Japan; in Takasaki, Empire of Japan (present-day Japan) (d. 2019){{citation needed|date=March 2025}}
• Frank Balistrieri, American gangster, boss of the Milwaukee crime family from 1961 to 1983; in Milwaukee, United States (d. 1993){{citation needed|date=March 2025}}
• Died: Robert A. Little, 22, Australian air force officer, commander of the No. 208 and No. 203 Squadrons, recipient of the Distinguished Service Order, Distinguished Service Cross and Croix de guerre; killed in action (b. 1895){{citation needed|date=March 2025}}

• Armenia and Azerbaijan both declared independence.{{cite book| last=Azadian| first=Edmond Y.| title=History on the Move: Views, Interviews and Essays on Armenian Issues| year=1999| publisher=[s.n.] | isbn=9780814329160| page=[https://books.google.com/books?id=KGciVUhpzXUC&pg=PA108 108]}}{{cite book| last=Adalian| first=Rouben Paul| title=Historical dictionary of Armenia| year=2010| publisher=Scarecrow Press| location=Lanham, MD| isbn=9780810874503|page=[https://books.google.com/books?id=QS-vSjHObOYC&pg=PA418 418]| edition=2nd| author-link=Rouben Paul Adalian}}{{cite book | last=Kazemzadeh | first=Firuz| author-link=Firuz Kazemzadeh |title=The Struggle for Transcaucasia: 1917-1921 |publisher=The New York Philosophical Library |year= 1951 | isbn=0-8305-0076-6 |pages=124, 222, 229, 269–270}}
• Germany and Georgia signed a treaty at the Black Sea port of Poti, which was to guarantee Germany would protect Georgia's sovereignty from the growing Soviet Russia.{{cite book| last1=Lang| first1=David Marshall| title=A Modern History of Georgia| url=https://archive.org/details/modernhistoryofg00lang| url-access=registration| date=1962| publisher=Weidenfeld and Nicolson.| location=London| pages=[https://archive.org/details/modernhistoryofg00lang/page/207 207–8]}}
• Battle of Karakilisa – Ottoman forces failed to break out of Karakilisa, Armenia and subsequently retreated.Walker 1980, p. 254
• Battle of Cantigny – The first military engagement for Americans occurred when the 1st Infantry Division attacked and captured the German-held village of Cantigny, France. American casualties were 1,603 while the Germans had 1,400 casualties and 250 captured.{{cite book |last=Sandler|first=Stanley | title = Ground Warfare: An International Encyclopedia, Volume 1|year=2002| publisher = ABC-CLIO| isbn= 9781576073445|page=150}}{{cite book |last=Zabecki| first=David T. | author-link = David T. Zabecki| title = Germany at War: 400 Years of Military History [4 volumes]: 400 Years of Military History|year=2014| publisher = ABC-CLIO| isbn= 9781598849813 |page=222}}
• The Ministry of Foreign Affairs for the government of Azerbaijan was established.{{cite web | url=http://www.azerbaijan.az/_StatePower/_MinistersCabinet/_ministersCabinet_e.html | title=THE MINISTRY OF FOREIGN AFFAIRS OF THE REPUBLIC OF AZERBAIJAN | access-date=2010-11-08 | archive-url=https://web.archive.org/web/20101119222916/http://azerbaijan.az/_StatePower/_MinistersCabinet/_ministersCabinet_e.html | archive-date=2010-11-19 | url-status=dead }}
• The city of Manteca, California was established.{{Cite web |url=http://www.calafco.org/docs/Cities_by_incorp_date.doc| title=California Cities by Incorporation Date |format=Word |publisher=California Association of Local Agency Formation Commissions| url-status=dead| archive-url=https://web.archive.org/web/20141103002921/http://www.calafco.org/docs/Cities_by_incorp_date.doc | archive-date=November 3, 2014}}
• The sports club Ottestad was established in Ottestad, Norway. It now offers association football, handball, cross-country skiing and cycling.{{cite web |url=http://www.fotball.no/Community/Klubber/Home/?fiksId=272 | language=no |title=Ottestad IL |work=fotball.no |publisher=Football Association of Norway |access-date=11 May 2012}}
• The film romantic comedy Bound in Morocco, starring Douglas Fairbanks and directed by Allan Dawn, was released through Famous Players–Lasky, becoming one of the top 10 grossing films of the year and the second hit for Fairbanks.{{cite web| url=http://www.silentera.com/PSFL/data/B/BoundInMorocco1918.html| title=Bound in Morocco (1918)| publisher=silentera.com| access-date=May 27, 2013}}{{cite book| title=Focus on Film, Issues 1-12| year=1970| publisher=Tantivy Press| page=28}}
• Born:
• Johnny Wayne, Canadian comedian, member of the popular comedic duo Wayne and Shuster; as Louis Weingarten, in Toronto, Canada (d. 1990){{citation needed|date=March 2025}}
• John Birch, American army officer and missionary, recipient of the U.S. Army Distinguished Service Medal and two-time recipient of the Legion of Merit, namesake for the John Birch Society; in Landour, British India (present-day India) (d. 1945, killed in action){{citation needed|date=March 2025}}
• John McKeithen, American politician, 49th Governor of Louisiana; in Grayson, Louisiana, United States (d. 1999){{citation needed|date=March 2025}}

• Battle of Abaran – After two days of counterattacks, the Armenians inflicted enough heavy casualties on the Ottoman Army to force them back towards Hamamlu, Armenia.Murgul 2007, p. 55
• Battle of Skra-di-Legen – Greek forces supported by the French bombarded fortified Bulgarian positions at Skra, Greece.Grigorios Dafnis, Sofoklis Eleftheriou Venizelos (Athens: Ikaros, 1970) pp. 44–47
• Born: Bert Corona, Mexican-American labor activist, leading member of the Congress of Industrial Organizations and the Chicano Movement in the 1960s; as Humberto Noé Corona (d. 2001){{citation needed|date=March 2025}}

• The Kuban Soviet Republic and Black Sea Soviet Republic merged into one Soviet republic.{{cite book |last=Азаренкова |first=А. С. |author2=И. Ю. Бондарь |author3=Н. С. Вертышева |title=Основные административно-территориальные преобразования на Кубани (1793–1985 гг.) |orig-year=1986 |year=1986 |publisher=Краснодарское книжное издательство |language=ru |page=394}}
• Third Battle of the Aisne – German forces advanced on Paris, capturing 50,000 Allied soldiers and over 800 guns.Hart 2008, p. 283
• Battle of Skra-di-Legen – Greek forces captured the Bulgarian fort at Skra, Greece, taking 2,045 prisoners and inflicting 600 casualties. Allied casualties were 441 killed, 2,227 wounded and 164 missing.Grigorios Dafnis, Sofoklis Eleftheriou Venizelos (Athens: Ikaros, 1970) pp. 44–47
• Birmingham College in Birmingham and Southern University in Greensboro, Alabama merged to become Birmingham–Southern College.{{cite web| title=History and Tradition| url=https://www.bsc.edu/about/tradition.html| website=BSC.edu| publisher=Birmingham-Southern College| access-date=4 December 2017}}
• The American Expeditionary Forces set up a second set of military hospitals in Châtel-Guyon, France, with Hospital No. 20 serving up to 2,000 wounded American soldiers.{{cite book|last1=Philadelphia War History Committee|title=Philadelphia in the war, 1914-1919|date=1922|publisher=Wynkoop Hallenbeck Crawford Co.|location=New York|url=https://archive.org/details/philadelphiainwo00philrich|pages=[https://archive.org/details/philadelphiainwo00philrich/page/206 206]–207}}
• The movie house Rialto Theater opened to the public in Omaha, Nebraska.{{cite book| last=Jeffrey S. Spencer [writer and researcher]| first=Kristine Gerber [project director]| title=Building for the ages : Omaha's architectural landmarks| year=2003| publisher=Omaha Books| location=Omaha, Neb.| isbn=0-9745410-1-X| edition=1st}}
• Born: Martin Lundström, Swedish Olympic cross-country skier, two-time gold medalist at the 1948 Winter Olympics and bronze medalist at the 1952 Winter Olympics; in Tvärliden, Sweden (d. 2016){{citation needed|date=March 2025}}
• Died:
• Georgi Plekhanov, 61, Russian philosopher, one of the first philosophers to adopt Marxism (b. 1856){{citation needed|date=March 2025}}
• Frederick Trump, 49, German-American business leader, founder of The Trump Organization, grandfather to Donald Trump (b. 1869){{citation needed|date=March 2025}}

• U.S. Navy troopship {{USS|President Lincoln|1907|6}} was torpedoed and sunk in the Atlantic Ocean by German submarine {{SMU|U-90||6}} with the loss of 26 of the 715 people on board. Survivors were rescued by fellow U.S. Navy ships {{USS|Smith|DD-17|6}} and {{USS|Warrington|DD-30|6}}.{{cite magazine|last=Foote|first=P.W.|title=Narrative of the "President Lincoln" |journal=Proceedings of the United States Naval Institute |date=July 1922 |volume=48| issue=7 |page=1086 |url=https://archive.org/stream/proceedingsofuni192248712unit#page/n9/mode/2up}}
• Royal Navy destroyer {{HMS|Fairy|1897|6}} rammed and sunk German submarine {{SMU|UC-75||6}} in the North Sea but foundered herself and had to be abandoned.{{cite Uboat.net|name=UC 75|id=UC+75|type=1sub}}
• Czech nationalist leader Tomáš Masaryk led the signing of an agreement between Czech and Slovak expats in Pittsburgh to unite as one nation.Votruba M. [http://www.pitt.edu/~votruba/qsonhist/pittsburghagreement.html "Pittsburgh Agreement"] University of Pittsburgh, Slovak Studies Program. Accessed 28 October 2013
• Lieutenant General John Monash took command of the Australian Corps, the largest corps on the Western Front.{{Citation |last=Perry |first=Roland |title=Monash: The Outsider Who Won A War |author-link=Roland Perry | location=Milsons Point, New South Wales |publisher=Random House |year=2004 |isbn=1-74051-364-9 |page=xiii}}
• American pilot Douglas Campbell scored his fifth victory, becoming the first ace from an American-trained unit.{{cite book| last1=Franks| first1=Norman| title=Nieuport Aces of World War 1| url=https://archive.org/details/nieuportacesworl01fran| url-access=limited| date=2000| publisher=Osprey Publishing| isbn=978-1-85532-961-4| page=[https://archive.org/details/nieuportacesworl01fran/page/n72 72]}}
• The football club Hebar Pazardzhik was established in Pazardzhik, Bulgaria.{{cite web| title=History-The Beginning| url=http://hebarfc.com/%D0%B8%D1%81%D1%82%D0%BE%D1%80%D0%B8%D1%8F/|website=Hebar FC|publisher=Football Club Hebar| access-date=21 December 2017| language=bg}}
• Born: Vilho Ylönen, Finnish shooter, silver medalist at the 1952 Summer Olympics and bronze medalist at the 1956 Summer Olympics; in Hankasalmi, Finland (d. 2000){{citation needed|date=March 2025}}

{{reflist|2}}

{{Events by month links}}

1918

*1918-05