- Jan 5 Central America proclaims annexation to Mexican Empire
- Jan 7 1st printing in Hawaii of a ceremonial broadside for King Kamehameha II by Elisha Loomis
- Jan 7 Liberia colonized by the American Colonization Society
- Jan 13 The design of the Greek flag is adopted by the First National Assembly at Epidaurus
- Jan 14 Greek War of Independence: Acrocorinth is captured by Theodoros Kolokotronis and Demetrius Ypsilanti
- Jan 15 Greek War of Independence: Demetrius Ypsilanti is elected president of the legislative assembly.
- Feb 4 Free American Blacks settle Liberia, West Africa
- Feb 9 American Indian Society organizes
- Feb 9 Haiti invades the newly founded Dominican Republic.
- Feb 23 Boston, Massachusetts, is incorporated as a city
- Mar 9 Charles Graham of NY granted first US patent for artificial teeth
- Mar 19 Boston, Massachusetts incorporated as a city
- Mar 22 NY Horticultural Society founded
- Mar 30 Congress combines East & West Florida into Florida Territory
- Mar 31 Massacre of the population of the Greek island of Chios by soldiers of the Ottoman Empire following a rebellion attempt, (later depicted by artist Eugène Delacroix)
- May 1 John Phillips becomes 1st mayor of Boston
Battle of Pichincha
May 24 Battle of Pichincha, Simón Bolívar secures the independence of Ecuador from Spain
- May 30 George Wilson and Joe LaRoche betray a planned slave revolt organized by Denmark Vesey in Charleston, South Carolina, confirming an earlier warning from Peter Prioleau. 35 Black people are later hanged. (date is approximate)
Event of Interest
Jun 6 Alexis St. Martin shot in the stomach and treated by physician William Beaumont on Mackinac Island. Leads Beaumont to conduct digestion experiments through hole in St. Martin's stomach.
- Jun 9 Charles Graham of New York patents porcelain false teeth
Event of Interest
Jun 14 Charles Babbage proposes a "difference engine" in a paper to the Royal Astronomical Society entitled "Note on the application of machinery to the computation of astronomical and mathematical tables"
- Jun 16 Denmark Vesey (aka Telemaque) Black American carpenter accused of planning a slave rebellion in South Carolina; tried and convicted, later executed by hanging
- Jun 18 Part of US-Canadian boundary determined
- Jun 21 Slave revolt leaders Denmark Vesey and Peter Poyas arrested in South Carolina
- Jul 2 Denmark Vesey (aka Telemaque), accused of planning a slave rebellion in South Carolina, dies by hanging at approximately 55
- Jul 8 Chippewas turn over huge tract of land in Ontario to the United Kingdom
- Jul 14 Date planned for the slave revolt in Charleston, South Carolina by Denmark Vesey and Peter Poyas (plot already uncovered in June)
Royal Coronation
Jul 25 General Agustin de Iturbide crowned Agustin I, 1st Emperor of Mexico
- Jul 26 Secret meeting of Simón Bolívar and Jose de San Martin
- Jul 30 James Varick becomes 1st bishop of African Methodist Episcopal Zion Church
- Aug 10 Antioch Syria, hit by Earthquake; about 20,000 die
- Sep 7 Pedro I, son of King Joao VI declares Brazil's independence from Portugal (National Day)
Rosetta Stone
Sep 27 French scholar Jean-François Champollion announces he has deciphered Egyptian hieroglyphics using the Rosetta Stone
- Oct 8 First eruption of Galunggung in Java sends boiling sludge into valley
- Oct 12 Second eruption of Galunggung in Java destroys summit of mountain
- Oct 19 In Parnaíba; Simplício Dias da Silva, João Cândido de Deus e Silva and Domingos Dias declare the independent state of Piauí
- Oct 20 1st edition of London Sunday Times
- Oct 26 King Willem I requires inhabitants of Brussels to use Dutch language
- Dec 1 Dom Pedro crowned emperor of Brazil
- Dec 2 In San Salvador, a congress proposes incorporation into US
- Dec 6 Veterinary school in Utrecht opens
- Dec 12 Mexico officially recognized as an independent nation by US