Decades: 1750s 1760s 1770s 1780s 1790s - 1800s - 1810s 1820s 1830s 1840s 1850s
Years: 1799 1800 1801 1802 1803 - 1804 - 1805 1806 1807 1808 1809
January 1 - End of French rule in Haiti
June 15 - The Twelfth Amendment to the U.S. Constitution ratified by New Hampshire, and arguably becomes effective (subsequently vetoed by the Governor of New Hampshire)
July 27 - The Twelfth Amendment to the U.S. Constitution ratified by Tennessee, removing doubt surrounding adoption.
February 15 - New Jersey becomes the last northern state to abolish slavery
February 16 - First Barbary War: Stephen Decatur leads a raid to burn the pirate-held frigate Philadelphia.
February 21 - The first self-propelling steam engine or steam locomotive makes its outing at the Pen-y-Darren ironworks in Wales. Designed by Richard Trevithick, a Cornishman
March 10 - Louisiana Purchase: In St. Louis, a formal ceremony is conducted to transfer ownership of Louisiana Territory from France to the United States.
March 21 - Code Napoleon adopted as French civil law
May 14 - The Lewis and Clark Expedition departs from Camp Dubois and begin their historic journey by traveling up the Missouri River.
May 18 - Napoleon Bonaparte is proclaimed Emperor of France by the French Senate.
August 20 - Lewis and Clark Expedition: The "Corps of Discovery", whose purpose is to explore the Louisiana Purchase, suffers it first and last death when Sergeant Charles Floyd dies, apparently from acute appendicitis.
November - Thomas Jefferson defeats Charles C. Pinckney in U.S. presidential election
November 30 - The Jeffersonian Republican-controlled United States Senate begin an impeachment trial against Federalist-partisan Supreme Court of the United States Justice Samuel Chase (he was charged with political bias but was acquitted by the Senate of all charges on March 1, 1805).
December 12 - Spain declares war on Britain
December 2 - At Notre Dame Cathedral in Paris, Napoleon Bonaparte is crowned as the first Emperor of France in a thousand years (the Napoleonic Code is adopted).
Pere Lachaise Cemetery a 118 acre cemetery in Paris, France was founded.
Year in topic
1804 in literature
1804 in music
March 14 - Johann Strauss I, Austrian composer
March 17 - Jim Bridger, pioneer (+ 1881)
July 1 - George Sand (Amantine Aurore Lucile Dupin), writer
July 4 - Nathaniel Hawthorne, writer
July 28 - Ludwig Feuerbach, German Philosopher
November 23 - Franklin Pierce, 14th president of the United States
December 21 - Benjamin Disraeli, British politician, writer
February 12 - Immanuel Kant, German philosopher
September 4 - Richard Somers, American naval officer\n