Millennia:	2nd millennium
Centuries:	18th century - 19th century - 20th century
Decades:	1790s 1800s 1810s - 1820s - 1830s 1840s 1850s
Years:	1820 1821 1822 1823 1824 1825 1826 1827 1828 1829
Categories:	Births - Deaths - Architecture Establishments - Disestablishments

Events and trends

• Nationalistic independence helped reshape the world during this decade:
  • Greece gains independence from the Ottoman Empire in the Greek War of Independence (1821-1827).
  • Several countries declared their independence from Spain and Portugal:
    • The Republic of Gran Colombia under President Simón Bolívar (1819 - 1828) expands over South America
    • Mexico (1821)
    • Brazil (1822)
• The United Provinces of Central America were formed in 1823.
• Invention of the photograph.
• United States (1825) The Erie Canal opens - passage from Albany, New York to Lake Erie and the Ohio and Erie Canal is dug to extend settlement access and commercial traffic to the Ohio River.
• Temperance movement emerges in U.S.
• Americo-Liberians begin to settle in the Colony of Liberia with the support of the American Colonization Society

World leaders

• Emir Dost Mohammad Khan (Afghanistan)
• Supreme director José Rondeau (Argentina)
• Acting supreme director Juan Pedro Julián Aguirre y López de Anaya (Argentina)
• President Bernardino Rivadavia (Argentina)
• President Vicente López y Planes (Argentina)
• General Manuel Dorrego (Argentina)
• General Juan Manuel de Rosas (Argentina)
• Emperor Francis II (Austria)
• Chancellor Klemens Wenzel von Metternich (Austria)
• Sheikh Sulman ibn Ahmad Al Khalifah (Bahrain)
• Sheikh Khalifah ibn Sulman Al Khalifah (Bahrain)
• Administrative leader Tendzin Drugdra (Bhutan)
• Administrative leader Choki Gyaltshen (Bhutan)
• President Simón Bolívar (Bolivia)
• President Antonio José de Sucre (Bolivia)
• President José María Pérez (Bolivia)
• President José Miguel de Velasco (Bolivia)
• President Pedro Blanco (Bolivia)
• President Andrés de Santa Cruz (Bolivia)
• Emperor Pedro I (Brazil)
• Sultan Muhammad Kanzul Alam (Brunei)
• Sultan Muhammad Alam (Brunei)
• Sultan Omar Ali Saifuddin II (Brunei)
• King Ang Chan II (Cambodia)
• President Bernardo O'Higgins (Chile)
• President Agustín Eyzaguirre (Chile)
• Provisional triumvirate of the three provinces Congreso de Plenipotenciarios (Chile)
• Interim Supreme Director Ramón Freire (Chile)
• Acting Supreme Director Diego José Benavente (Chile)
• President Manuel Blanco Encalada (Chile)
• President Francisco Antonio Pinto (Chile)
• President Francisco Ramón Vicuña (Chile)
• President José Tomás Ovalle (Chile)
• Emperor Daoguang (China)
• President Simón Bolívar (Greater Colombia)
• King Frederick VI (Denmark)
• Governor Muḩammad ‘Alī (Egypt)
• Emperor Iyoas II (Ethiopia)
• Emperor Gigar (Ethiopia)
• Emperor Baeda Maryam III (Ethiopia)
• President José Cecilio del Valle (Federal Republic of Central America)
• President Manuel José Arce (Federal Republic of Central America)
• President José Francisco Barrundia (Federal Republic of Central America)
• King Louis XVIII (Restoration France)
• King Charles X (Restoration France)
• Governor Ioannis Kapodistrias (Greece)
• King Henri Christophe (Haiti)
• President Jean Pierre Boyer (Haiti)
• Pope Pius VII
• Pope Leo XII
• Shogun Tokugawa Ienari (Japan)
• Khan Omar Beg (Kokand)
• Khan Mohammed Ali (Kokand)
• Emperor Sunjo (Korea)
• Emir Jaber I Al-Sabah (Kuwait)
• Emperor Agustín de Iturbide (Mexico)
• President Guadalupe Victoria (Mexico)
• President Vicente Guerrero (Mexico)
• President José María Bocanegra (Mexico)
• President Pedro Vélez (Mexico)
• Sultan Slimane (Morocco)
• Sultan Abderrahmane (Morocco)
• Padshah Akbar II (Mughal Empire)
• Fath Ali Shah of Qajar dynasty (Persia)
• King Frederick William III (Prussia)
• Maharaja Ranjit Singh (Sikh Empire, Punjab)
• Emperor Alexander I (Russia)
• Emperor Nicholas I (Russia)
• King Victor Emmanuel I (Sardinia)
• King Charles Felix (Sardinia)
• King Rama II (Siam)
• King Rama III (Siam)
• King Ferdinand VII (Spain)
• King Charles XIV John (Sweden)
• Pasha Yusuf Karamanli (Tripoli)
• King George IV (United Kingdom of Great Britain and Ireland)
• King William I (United Kingdom of the Netherlands)
• President James Monroe (United States)
• President John Quincy Adams (United States)
• Emperor Minh Mang (Vietnam)