The 1840s

1840 CE76 entries

• January 22 – British colonists reach New Zealand, officially founding the settlement of Wellington.
• April 2 – The Washingtonian movement for teetotalism is founded by a group of alcoholics in Baltimore, Maryland.
• September 10 – Ottoman and British troops bombard Beirut, and land troops on the coast, to pressure Egyptian Muhammad Ali to retreat from the country.

1841 CE67 entries

• June 21 – St. John's College, later Fordham University, is founded in The Bronx by Jesuits.
• October 16 – Queen's University is founded in Kingston, Ontario, by Rev. Thomas Liddell, who carries a Royal Charter from Queen Victoria, and becomes the school's first principal.
• December 20 – The first multilateral treaty for the suppression of the African slave trade, the Treaty for the Suppression of the African Slave Trade, signed in London by the representatives of Austria, Britain, France, Prussia and Russia.

1842 CE80 entries

• June 18 – Education in Sweden: A primary school system is established in Sweden.
• August 29 – The Treaty of Nanking, an unequal treaty between the United Kingdom and Qing dynasty China, ends the First Opium War, and establishes Hong Kong as a British colony (later a British dependent territory until 1997).
• November 26 – The University of Notre Dame in Notre Dame, Indiana (United States) is established by Father Edward Sorin, of the Roman Catholic Congregation of Holy Cross.

1843 CE86 entries

• March 15 – Victoria, British Columbia, is founded by the Hudson's Bay Company as a trading post and fort.
• July – Margaret Fuller's "The Great Lawsuit. Man versus Men. Woman versus Women" appears in The Dial magazine in the United States.
• September – Ada Lovelace translates and expands Menabrea's notes on Charles Babbage's Analytical Engine, including an algorithm for calculating a sequence of Bernoulli numbers, regarded as the world's first computer program.

1844 CE71 entries

1845 CE76 entries

• February 28 – The United States Congress approves the annexation of Texas.
• 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.
• 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.

1846 CE77 entries

• February 4 – Led by Brigham Young, many Mormons in the U.S. begin their migration west from Nauvoo, Illinois, to the Great Salt Lake in what becomes Utah.
• September 7 – The portion of the District of Columbia in the United States that was ceded by Virginia in 1790 is re-ceded to Virginia.
• November 17 – Carl Zeiss, a major worldwide optoelectronics and digital camera brand, is founded in Thuringia, Germany.

1847 CE80 entries

• March 14 – Verdi's opera Macbeth premieres at the Teatro della Pergola, in Florence, Italy.
• April 25 – The , carrying Irish emigrants from Derry bound for Quebec, is wrecked off Islay, with only three survivors from more than 250 on board.
• June – E. H. Booth & Co. Ltd, which becomes the northern England supermarket chain Booths, is founded when tea dealer Edwin Henry Booth, 19, opens a shop called "The China House" in Blackpool.

1848 CE124 entries

1849 CE95 entries

• January 8 – Hungarian Revolution of 1848: Romanian armed groups massacre 600 unarmed Hungarian civilians, at Nagyenyed.
• March – The Frankfurt Parliament completes its drafting of a liberal constitution, and elects Frederick William IV emperor of the new German national state.
• April 1 – Hungarian Revolution of 1848: The Hungarian Revolutionary Army, under the leadership of Arthur Görgey, starts the victorious Spring Campaign, which leads to the liberation of much of Hungary from the Austrian forces.