January – March
- February 11 – Fort Meigs: Leftwich is not successful, and when he leaves, Major Amos Stoddard takes the command of the post.
- February 26 – The Secretary of War orders Colonel R. M. Johnson to get ready a group of mounted volunteers who will serve from 4–6 months after being called into active service.
- February late– General Harrison sends out an expedition to burn the British vessels at Malden by going across Lake Erie via the Bass Islands in sleighs, but the ice is not hard enough and the expedition returns.
- March 22 – Col. R. M. Johnson puts out an order for raising a regiment of mounted volunteers in Kentucky.
April – June
- April 8 – Colonel James Ball arrives at Fort Meigs with 200 dragoons.
- April 27 - War of 1812: Battle of York - United States troops raid, destroy, but do not hold the capital of Ontario, York (present day Toronto, Ontario).
- May 2 – Napoleon wins the Battle of Lützen
- May 11– Gregory Blaxland, William Lawson and William Wentworh left on an expedition to cross the Blue Mountains
- May 20-May 21 – Napoleon wins the Battle of Bautzen
- May 27 – War of 1812: In Canada, United States forces capture Fort George.
- June 6 – War of 1812: Battle of Stoney Creek – A British force of 700 under John Vincent defeat an American force three times its size under William Winder and John Chandler. Gregory Blaxland, William Lawson and William Wentworh succeeded in crossing the Blue Mountains and returned home.
- June 21 – Peninsular War: Battle of Vitoria – A British, Spanish, and Portuguese force of 78,000 with 96 guns under Wellington defeats a French force of 58,000 with 153 guns under Joseph Bonaparte to end the Peninsular War.
Undated
- Russian troops reach and take Berlin without a fight after the French garrison evacuated (sent everyone out) the city.
- Mathieu Orfila publishes his groundbreaking Trait des poisons, formalizing the field of toxicology.
- George Hamilton-Gordon serves as ambassador expert in Vienna.
- After the death of his father Wossen Seged, Sahle Selassie arrives at the capital Qundi before his other brothers, and is made Meridazmach of Shewa.
- The Philomathean Society of the University of Pennsylvania is founded. It is the oldest continuously existing literary society in the United States.
- January 19 – Sir Henry Bessemer, English inventor (d. 1898)
- January 21 – John C. Frémont, American soldier and explorer (d. 1890)
- January 26 – Juan Pablo Duarte, Founder of the Dominican Republic (d. 1876)
- February 11 – Otto Ludwig, German writer (d. 1865)
- February 15 – Frederick Holbrook, Vermont governor (d. 1909)
- March 18 – Christian Friedrich Hebbel, German poet and playwright (d. 1863)
- March 19 – David Livingstone, English missionary and explorer (d. 1873)
- March 21 – James Strang, Mormon splinter group leader (d. 1856)
- March 27 – Nathaniel Currier, American illustrator (d. 1888)
- April 23 – Stephen A. Douglas, U.S. Senator from Illinois and Presidential candidate (d. 1861)
- May 5 – Soren Kierkegaard, Danish philosopher (d. 1855)
- May 21 – Robert Murray M'Cheyne, Scottish clergyman (d. 1843)
- May 22 – Richard Wagner, German composer (d. 1883)
- June 24 – Henry Ward Beecher, American clergyman and reformer (d. 1887)
- July 19 – Samuel M. Kier, American industrialist (d. 1874)
- September 17 – John Sedgwick, Union Army General, American Civil War (d. 1864)
- October 10 – Giuseppe Verdi, Italian composer (d. 1901)
- October 17 – Georg Büchner, German playwright (d. 1837)
- December 13 – David Spangler Kaufman, U.S. Congressman from Texas (d. 1851)
- December 19 – Thomas Andrews, Irish chemist (d.1885)
Unknown dates
- Abbas I, Pasha of Egypt (d. 1854)
- John Miley, American Methodist theologian (d. 1895)
- Gerardo Barrios, President of El Salvador (d. 1865)
- January 6 – Louis Baraguey d'Hilliers, French general (born 1764)
- January 20 – Christoph Martin Wieland, German writer (born 1733)
- February 13 – Samuel Ashe, Governor of North Carolina (born 1725)
- February 26 – Robert Linvingston, American signer of the Declaration of Independence (born 1746)
- April 10 – Joseph Louis Lagrange, Italian mathematician (born 1746)
- April 27 – Zebulon Pike, American general (born 1779)
- April 28 – Mikhail Illarionovich Kutuzov, Russian field marshal (born 1745)
- May 1 – Jean-Baptiste Bessières, French marshal (killed in combat) (born 1768)
- May 23 – Geraud Duroc, French general (mortally wounded in battle) (born 1772)
- June 6 – Alexandre-Théodore Brongniart, French architect (born 1739)
- June 17 – Charles Middleton, 1st Baron Barham, English sailor and politician (born 1726)
- June 28 – Gerhard von Scharnhorst, Prussian general (born 1755)
- July 29 – Jean-Andoche Junot, French general (suicide) (born 1771)
- August 11 – Henry James Pye, English poet (born 1745)
- August 15-Abigail Amelia, First born daughter Of John and Abigail Adams (born 1765)
- August 23 – Alexander Wilson, Scottish-born ornithologist (born 1766)
- September 2 – Jean Victor Marie Moreau, French general (mortally wounded in battle) (born 1763)
- October 5 – Tecumseh, Shawnee leader
- October 19 – Józef Antoni Poniatowski, Polish prince and Marshal of France (friendly fire) (born 1763)
- November 12 – Jean de Crévecoeur, French-American writer (born 1735)
- December 24 – Empress Go-Sakuramachi of Japan (born 1740)
Unknown dates
- Wossen Seged, Meridazmach of Shewa (murdered) (born 1808)
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