1806 1807 1808 - 1809 - 1810 1811 1812
| Decades: |
1770s 1780s 1790s - 1800s - 1810s 1820s 1830s
| Centuries: |
18th century - 19th century - 20th century
- January 16 - Peninsular War: The British defeat the French at the Battle of Corunna.
- February 3 - Illinois Territory was created.
- February 11 - Robert Fulton patents the steamboat.
- February 20 - A decision by the Supreme Court of the United States states that the power of the federal government is greater than any individual state.
- March 4 - James Madison succeeds Thomas Jefferson as the President of the United States
- March 29 - At the Diet of Porvoo, Finland's four Estates pledge allegiance to Alexander I of Russia, commencing the secession of the Grand Duchy of Finland from Sweden
- April 9 - Tyroleans rise against French and Bavarian occupation - they include militia lead by Andreas Hofer
- April 19 - Battle of Raszyn between armies of Austria (attackers) and Duchy of Warsaw (defenders) as a part of struggles of the Fifth Coalition (1809). Austrian army was defeated.
- May - Napoleon captures Vienna, is excommunicated, imprisons pope Pius VII
- May 5 - Mary Kies is the first woman to be awarded a patent
- May 5 - The Swiss canton of Aargau denies Jews citizenship.
- May 17 - Napoleon I of France orders the annexation of the Papal States to the French empire.
- June 6 - Sweden promulgates a new Instrument of Government, which restores political power to the Riksdag of the Estates after authoritarian rule since 1772.
- June 7 - Shoja Shah of Afghanistan signs a treaty with the British. Only weeks later, he is succeeded by Mahmud Shah
- September 17 - Peace between Russia and Sweden in the Finnish War. The territory to become the Grand Duchy of Finland is ceded to Russia by the Treaty of Fredrikshamn.
- October 11 - Along the Natchez Trace in Tennessee, explorer Meriwether Lewis dies under mysterious circumstances at an inn called Grinder's Stand.
- USS Constitution (Old Ironsides) is recommissioned as flagship of the North Atlantic Squadron.
- Louis Poinsot describes the two remaining Kepler-Poinsot solids.
- Lamarck publishes Philosophie Zoologique, outlining the concept of evolution.
- First running of the Two Thousand Guineas Stakes horse race in England.
- January 4 - Louis Braille, teacher, developed writing system for the blind (d. 1852).
- January 15 - Pierre-Joseph Proudhon, anarchist (d. 1864))
- January 19 - Edgar Allan Poe, US writer (d. 1849)
- February 3 - Felix Mendelssohn, composer (d. 1847)
- February 12 - Abraham Lincoln, US president (d. 1865)
- February 12 - Charles Darwin, British naturalist (d. 1882)
- February 15 - Cyrus McCormick, inventor (d. 1884)
- March 31 - Nikolai Gogol, writer (d. 1852)
- June 4 – Columbus Delano, American statesman (d. 1896)
- June 8 - Richard Wigginton Thompson, congressman
- August 6 - Alfred Lord Tennyson, British poet
- August 8 - Heinrich Abeken, German theologian
- August 27 - Hannibal Hamlin, US politician
- August 29 - Oliver Wendell Holmes, Sr., physician, writer (d. 1894)
- October 22 - Volney E. Howard, American politician (d. 1889)
- December 24 - Christopher Houston, American frontiersman
- December 29 - William Ewart Gladstone, British liberal politician
- Hermann Gunter Grassmann, Prussian mathematician
- March 25 - Anna Seward, English writer
- May 13 - Beilby Porteus, Bishop of London, leading abolitionist
- June 8 - Thomas Paine, writer of Common Sense
- August 18 - Matthew Boulton, pioneering industrialist and member of the Lunar Society
- Nikolaj Abraham Abildgaard, Danish painter
- Joseph Haydn, Austrian composeraf:1809