Decades: 1770s 1780s 1790s 1800s 1810s - 1820s - 1830s 1840s 1850s 1860s 1870s
Years: 1815 1816 1817 1818 1819 - 1820 - 1821 1822 1823 1824 1825
January 1 - Constitutionalist military insurrection at Cadiz leads to summoning of Spanish parliament (March 7) and restoration of 1812 Constitution (March 8) by king Ferdinand VII.
January 29 - George the Prince Regent becomes king George IV of the United Kingdom, ending the period known as the English Regency.
January 30 - Edward Bransfield discovers Antarctica.
February 6 - 86 free African American colonists sail from New York City to Freetown, Sierra Leone.
February 23 - The Cato Street conspiracy is exposed. The principals are executed on May 1
March 3 & March 6 - The Missouri Compromise becomes law in the United States.
March 15 - Maine is admitted as the 23rd U.S. state.
Spring - Joseph Smith, Jr at age 14 claims to be visited in a vision by God and Jesus Christ (Tradition holds that this occurred on April 6)
July Constitutionalist revolution in the Kingdom of the Two Sicilies
August 24 - Constitutionalist insurrection at Oporto, Portugal; revolution in Lisbon, September 15
October 9 - Guayaquil declare independence from Ecuador.
October 25-November 20 - Congress of Troppau (Opava) between rulers of Russia, Austria and Prussia
November - James Monroe is re-elected, virtually unopposed.
November 17 - Captain Nathaniel Palmer becomes the first American to see Antarctica (the Palmer Peninsula was later named after him).
6th Edition of Encyclopaedia Britannica begins appearing.
Republic of Buenos Aires (Argentina) establishes penal colony in Falkland Islands.
Venus de Milo found on island of Melos.
Hans Christian Orsted discovers relationship between electricity and magnetism.
Year in topic
1820 in literature
1820 in science
January 17 - Anne Bronte, author
February 8 - William Tecumseh Sherman, soldier (+ 1891)
February 15 - Susan B. Anthony, US suffragist
February 28 - John Tenniel, illustrator
March 14 - Victor Emmanuel II of Italy
May 12 - Florence Nightingale, nurse (+ 1910)
May 27 - Mathilde Bonaparte, hostess and socialite
September 27 - Wilhelm Siegmund Teuffel, classical scholar
September 29 - Henry, Duke of Bordeaux, posthumous son of the Duke of Berry, future Comte de Chambord and claimant to the French throne
Harriet Tubman, anti-slavery resistance movement leader
January 29 - King George III of the United Kingdom
February 14 - Charles Ferdinand, Duke of Berry, stabbed on February 13
March 22 - Stephen Decatur, sailor
June 19 - Sir Joseph Banks, British naturalist and botanist
September 3 - Benjamin Latrobe, architect
Heads of states
Ottoman Empire - Mahmud II Sultan of the Ottoman Empire (1808-1839)
Prussia - Frederick William III King of Prussia (1797-1840)
Russia - Alexander I Tsar of Russia (1801-1825)\n