Events of 1843

January - March

• February 6 - The Virginia Minstrels perform the first minstrel show (Bowery Amphitheatre, New York City).
• February 11 - Giuseppe Verdi's opera I Lombardi premieres in Milan.
• February 14 - The event that inspired the Beatles song Being for the Benefit of Mr. Kite! is held in England.
• March 15 - Victoria, British Columbia, is founded by the Hudson's Bay Company as a trading post and fort.
• March 21 - The world does not end, contrary to the first prediction by American preacher William Miller.

April - June

• May 4 - Natal is proclaimed a British colony.
• May 18 - The disruption of the Church of Scotland takes place in Edinburgh.
• May 22 - The first major wagon train headed for the American Northwest sets out with one thousand pioneers from Elm Grove, Missouri on the Oregon Trail.
• May 23 - Chile takes possession of the Strait of Magellan.
• June 6 - In Barbados, Samuel Jackman Prescod is the first non-white person elected to the House of Assembly.

July - September

• July 1
• Ulysses S. Grant graduates from West Point 21st from a class of 39.
• John J. Peck graduates from West Point 8th from a class of 39.
• July 19 - The SS Great Britain is launched from Bristol.
• August 15 - Tivoli Gardens, one of the oldest still intact amusement parks in the world, opens in Copenhagen, Denmark.

October - December

• October 13 - In New York City, Henry Jones and 11 others found B'nai B'rith (the oldest Jewish service organization in the world).
• November 11 - Hans Christian Andersen's The Ugly Duckling is first published.
• November 28 - Ka La Ku'oko'a (Hawaiian Independence Day): The Kingdom of Hawai`i is officially recognized by the United Kingdom and France as an independent nation.
• December 19 - Charles Dickens' A Christmas Carol is first published.

Undated

• The world's first commercial Christmas cards are printed by Sir Henry Cole in London.
• James Joule quantifies the conversion of work into heat.
• The Danish government re-establishes the Althing in Iceland as an advisory body.
• The first tunnel under the Thames River is finished.
• Argentina supports Rosas of Uruguay and begins a siege of Montevideo.
• Quaternions are discovered by William Rowan Hamilton.
• The Economist is first published.
• Bishop's University is founded.
• Abbeville, Louisiana is founded by descendants of Acadians from Nova Scotia.
• Edgar Allan Poe's short story The Tell-Tale Heart is first published.
• Germans from the Black Forest region of Southern Baden migrate to Venezuela.
• The export of British textile machinery and other equipment is allowed.

Births

January - June

• January 8 - John H. Moffitt, American politician (d. 1926)
• January 10 - Frank James, American outlaw (d. 1915)
• January 29 - William McKinley, 25th President of the United States (d. 1901)
• April 4 - William Jackson, photographer (d. 1942)
• April 15 - Henry James, American writer (d. 1916)
• April 25 - Princess Alice of the United Kingdom, third child of Queen Victoria (d. 1878)
• May 21 - Charles Albert Gobat, Swiss politician, recipient of the Nobel Peace Prize (d. 1914)
• June 3 - King Frederick VIII of Denmark (d. 1912)
• June 9 - Bertha von Suttner, Austrian writer and pacifist, recipient of the Nobel Peace Prize (d. 1914)
• June 15 - Edvard Grieg, Norwegian composer (d. 1907)
• June 30 - Sir Ernest Satow, British diplomat and scholar (d. 1928)

July - December

• July 7 - Camillo Golgi, Italian physician, recipient of the Nobel Prize in Physiology or Medicine (d. 1926)
• July 29 - Johannes Schmidt, German linguist (d. 1901)
• August 1 - Robert Todd Lincoln, American statesman and businessman (d. 1926)
• August 20 - Christina Nilsson, Swedish operatic soprano (d. 1921)
• August 31 - Georg von Hertling, Chancellor of Germany (d. 1919)
• November 25 - Henry Ware Eliot, American industrialist, philanthropist and the father of T. S. Eliot (d. 1919)
• November 27 - Cornelius Vanderbilt II, American railway magnate (d. 1899)
• December 11 - Heinrich Hermann Robert Koch, German physician, recipient of the Nobel Prize in Physiology or Medicine (d. 1910)
• December 28 - Colonel Prentiss Ingraham, American author of dime fiction (d. 1904)
• date unknown - Owon, Korean painter (d. 1897)
• probable - Pierre Lallement, French inventor of the bicycle (d. 1891)

Deaths

January - June

• January 11 - Antoine Bournonville, French ballet dancer and choreographer (b. 1760)
• March 21
• Robert Southey, English poet (b. 1774)
• Guadalupe Victoria, Mexican revolutionary (b. 1786)
• March 25 - Robert Murray M'Cheyne, Scottish clergyman (b. 1813)
• March 27 - Karl Salomo Zachariae Von Lingenthal, German jurist (b. 1769)
• April 15 - Noah Webster, American lexicographer (b. 1758)
• April 17 - Samuel Morey, American inventor (b. 1762)
• May 28 - Noah Webster, lexicographer (b. 1758)
• June 1 - William Abbot, English actor (b. 1798)
• June 6 - Friedrich Hölderlin, German writer (b. 1770)

July - December

• July or August - Sequoyah, creator of the Cherokee syllabary (b. c. 1767)
• July 7 - John Holmes, American politician (b. 1773)
• July 14 - Miguel de Álava, Spanish soldier and statesman (b. 1770)
• September 11 - Joseph Nicollet, geographer (b. 1786)
• December 12 - King William I of the Netherlands (b. 1772)
• December 18 - Thomas Graham, Lord Lynedoch, British Governor-General of India (b. 1748)