1845

File: An Irish Peasant Family Discovering the Blight of their Store by Daniel MacDonald.jpg: Potato crops ruined in Ireland, starting the Great Famine.]]

File:Wpdms republic of texas.svg: U.S. annexes territory of the Republic of Texas.]]

Events

= January–March =

January 1 – The Philippines began reckoning Asian dates by hopping the International Date Line through skipping Tuesday, December 31, 1844. That time zone shift was a reform made by Governor–General Narciso Claveria on August 16, 1844, in order to align the local calendars in the country with the rest of Asia as trade interests with Imperial China, Dutch East Indies and neighboring countries increased, after Mexico became independent in 1821. The reform also applied to Caroline Islands, Guam, Marianas Islands, Marshall Islands, and Palau as part of the Captaincy General of the Philippines.{{Cite web|url=https://www.facebook.com/pvinta/photos/a.1924058474508083/2862176590696262/|title=CURRENT PH CALENDAR BEGINS|publisher=Project Vinta|date=January 1, 2021|language=EN|website=Facebook|access-date=April 19, 2023}}
January 10 – Elizabeth Barrett receives a love letter from the younger poet Robert Browning;{{cite book|editor=Jones, Neal T.|title=A Book of Days for the Literary Year|url=https://archive.org/details/bookofdaysforlit0jone|url-access=registration|location=New York; London|publisher=Thames and Hudson|year=1984|isbn=0-500-01332-2}} on May 20, they meet for the first time in London. She begins writing her Sonnets from the Portuguese.
January 23 – The United States Congress establishes a uniform date for federal elections, which will henceforth be held on the first Tuesday after the first Monday in November.
January 29 – The Raven by Edgar Allan Poe is published for the first time, in the New York Evening Mirror.
February 1 – Anson Jones, President of the Republic of Texas, signs the charter officially creating Baylor University (the oldest university in the U.S. state of Texas that still operates under its original name).
February 7 – In the British Museum, a drunken visitor smashes the Portland Vase, which takes months to repair.
February 28 – The United States Congress approves the annexation of Texas.
March 1 – President John Tyler signs a bill authorizing the United States to annex the Republic of Texas, subject to approval by the voters in the Republic. The territory claimed includes all of the future U.S. state of Texas, as well as portions of New Mexico, Oklahoma, Kansas, Colorado and Wyoming.
March 3
Florida is admitted as the 27th U.S. state.
For the first time, both houses of the United States Congress vote, by a two-thirds majority, to override a presidential veto in order to pass legislation.[http://history.house.gov/Historical-Highlights/1800-1850/The-first-congressional-override-of-a-presidential-veto/ Congress overrides presidential veto for first time]. history.house.gov
March 11 – The New Zealand Wars open with the Flagstaff War. Chiefs Kawiti and Hōne Heke lead 700 Maoris in the burning of the British colonial settlement of Kororareka (modern-day Russell, New Zealand).
March 13 – The Violin Concerto by Felix Mendelssohn premieres in Leipzig, with Ferdinand David as soloist.
March 17 – Stephen Perry patents the rubber band, in the United Kingdom.{{cite book|title=Penguin Pocket On This Day|publisher=Penguin Reference Library|isbn=0-14-102715-0|year=2006}}

= April–June =

April 7 – An earthquake destroys part of Mexico City, along with the nearby towns of Tlalpan and Xochimilco.
April 10 – The Great Fire of Pittsburgh destroys much of the American city of Pittsburgh.
April 20 – Ramón Castilla becomes president of Peru.
May 2 – Yarmouth suspension bridge in Great Yarmouth, England, collapses leaving around 80 dead, mostly children.{{cite web|title=The Great Yarmouth Suspension Bridge Disaster – May 2nd 1845|url=http://www.broadlandmemories.co.uk/documents/news/news_pre1900/gy_suspensionbridge_1845.pdf|work=Broadland Memories|access-date=2010-10-14|url-status=dead|archive-url=https://web.archive.org/web/20110718231354/http://www.broadlandmemories.co.uk/documents/news/news_pre1900/gy_suspensionbridge_1845.pdf|archive-date=2011-07-18}}
May 19 – HMS Erebus and HMS Terror, with 134 men, comprising Sir John Franklin's expedition to find the Northwest Passage, sail from Greenhithe on the Thames. They will last be seen in the summer, entering Baffin Bay.{{cite book|title=The Hutchinson Factfinder|publisher=Helicon|year=1999|isbn=1-85986-000-1|page=549}}
May 25 – A theater fire in Canton, China, kills 1,670.
May 30 – Fatel Razack ({{lang|ar-Latn|Fath Al Razack}}, 'Victory of Allah the Provider', {{Langx|ar|قتح الرزاق}}) is the first ship to bring indentured labourers from India to Trinidad and Tobago, landing in the Gulf of Paria with 227 immigrants.When the British decided they were going to bring Indians to Trinidad this year, most of the traditional British ship owners did not wish to be involved. The ship was originally named Cecrops, but upon delivery was renamed to Fath Al Razack. The ship left Calcutta on February 16.
May – Frederick Douglass's autobiographical Narrative of the Life of Frederick Douglass, an American Slave is published by the Boston Anti-Slavery Society.
June 8 – Former U.S. President Andrew Jackson, 78, dies at The Hermitage (Nashville, Tennessee).

= July–September =

July 26–August 10 – Isambard Kingdom Brunel's iron steamship Great Britain makes the transatlantic crossing from Liverpool to New York, the first screw propelled vessel to make the passage.{{cite book|last=Fox|first=Stephen|year=2003|title=Transatlantic: Samuel Cunard, Isambard Brunel, and the Great Atlantic Steamships|publisher=HarperCollins|isbn=978-0-06-019595-3|url-access=registration|url=https://archive.org/details/transatlanticsam00foxs}}{{cite web|title=Great Britain |url=http://www.theshipslist.com/pictures/Greatbritain.htm |work=The Ships List |access-date=2010-10-01 |url-status=dead |archive-url=https://web.archive.org/web/20100528131641/http://www.theshipslist.com/pictures/Greatbritain.htm |archive-date=May 28, 2010 }}
July 28 – HMS Terror and HMS Erebus of the Franklin Expedition go missing in the Davis Strait west of Greenland, while searching for the Northwest Passage.
August 4 – British emigrant barque Cataraqui is wrecked on King Island (Tasmania) with 400 people killed and only 9 survivors.{{cite news|title=Dreadful Shipwreck! Wreck of the Cataraqui Emigrant Ship, 800 tons|newspaper=Launceston Examiner|page=5|date=1845-09-17|url=http://nla.gov.au/nla.news-article36241486|accessdate=2011-08-21}}
August 9 – The Aberdeen Act is passed by the Parliament of the United Kingdom, empowering the British Royal Navy to search Brazilian ships, as part of the abolition of the slave trade from Africa.
August 19 – A tornado kills 200 people in France at Montville while destroying two large factories.

File:1845 08 28 Scientific American - Cover page Scientific American, first edition.jpg

August 28 – The journal Scientific American begins publication.
September 9 – Potato blight breaks out in Ireland,{{cite book|last=Palmer|first=Alan|last2=Palmer |first2=Veronica|year=1992|title=The Chronology of British History|publisher=Century Ltd|location=London|pages=267–268|isbn=0-7126-5616-2}}{{cite web|title=Phytophthora infestans|url=http://www.bbc.co.uk/northernireland/ashorthistory/archive/intro182.shtml|publisher=BBC|work=A Short History of Ireland|access-date=2012-08-05}} beginning the Great Famine.
September 18 – The Anglo-French blockade of the Río de la Plata is formally declared.
September 25 – The Phi Alpha Literary Society is founded, in Jacksonville, Illinois.

= October–December =

October 9 – The eminent and controversial Anglican, John Henry Newman, is received into the Roman Catholic Church.
October 10 – In Annapolis, Maryland, the Naval School (later renamed the United States Naval Academy) opens with 50 midshipmen and seven professors.
October 13 – A majority of voters in the Republic of Texas approve a proposed constitution that, if accepted by the United States Congress, will make Texas a U.S. state.
October 19 – Richard Wagner's opera Tannhäuser debuts at the Dresden Royal Court Theater.
October 21 – The New York Herald becomes the first newspaper to mention the game of baseball.
November 20 – Anglo-French blockade of the Río de la Plata – Battle of Vuelta de Obligado: The Argentine Confederation is narrowly defeated by an Anglo–French fleet on the waters of the Paraná River, but the victors suffer serious damage to their ships, and Argentina attracts political support in South America.
December 2 – Manifest destiny: U.S. President James K. Polk announces to Congress that the Monroe Doctrine should be strictly enforced, and that the United States should aggressively expand into the West.
December 11 – First Anglo-Sikh War: Sikh army crosses the Sutlej in the Punjab.
December 22–23 – Battle of Ferozeshah (Anglo-Sikh War): East India Company forces are victorious over those of the Sikh Empire.
December 27
Anesthesia is used for childbirth for the first time, by Dr. Crawford Long in Jefferson, Georgia.
American newspaper editor John L. O'Sullivan claims (in connection with the annexation of the Oregon Country) in The United States Magazine and Democratic Review that the United States should be allowed "the fulfillment of our manifest destiny to overspread the continent allotted by Providence for the free development of our yearly multiplying millions". It is the second time he uses the term manifest destiny (first in connection with the Republic of Texas in July – August), and it will have a huge influence on American imperialism in the following century.
December 29 – Texas is admitted as the 28th U.S. state.
December 30 – Queen's Colleges of Belfast, Cork, and Galway are incorporated in Ireland.

= Date unknown =

The Republic of Yucatán separates from Mexico for a second time.
Ephraim Bee reveals that the Emperor of China has given him a special dispensation: that he has entrusted him with certain sacred and mysterious rituals through Caleb Cushing, the U.S. Commissioner to China, to "extend the work and influence of the Ancient and Honorable Order of E Clampus Vitus" in the New World.{{cite web|title=E. Clampus Vitus|url=http://www.chamberbyphone.mobi/mobi_about_us.php?mid=45841787|year=2010|access-date=2010-10-01|archive-url=https://web.archive.org/web/20110722220507/http://www.chamberbyphone.mobi/mobi_about_us.php?mid=45841787|archive-date=July 22, 2011|url-status=dead|df=mdy-all}}
Friedrich Engels' treatise The Condition of the Working Class in England is published in Leipzig as {{lang|de|Die Lage der arbeitenden Klasse in England}}.
Heinrich Hoffmann publishes a book ({{lang|de|Lustige Geschichten und drollige Bilder}}), introducing his character, Struwwelpeter, in Germany.
The Ancient and Accepted Rite for England and Wales and its Districts and Chapters Overseas is founded{{Vague|date=July 2013}} in Freemasonry.
Eugénie Luce founds the Luce Ben Aben School in Algiers.{{cite web|url=http://www.wdl.org/en/item/8800/|title=Luce Ben Aben School of Arab Embroidery I, Algiers, Algeria|website=World Digital Library|year=1899|access-date=2013-09-26}}