1820s

{| align=right cellpadding=3 id=toc style="margin-left: 15px;"\n|- \n| align="center" | Centuries:
18th century - 19th century - 20th century

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\n|-\n| align="center" colspan=2 | Decades:
1790s 1800s 1810s - 1820s - 1830s 1840s 1850s\n|- \n| align="center" colspan=2 | Years:
1820 1821 1822 1823 1824 1825 1826 1827 1828 1829\n|}\nEvents and Trends\n*Nationalistic independence movements helped reshape the world during this decade:\n**Greece declares independence from the Ottoman Empire (1821).\n**Several countries declared their independence from Spain and Portugal:\n***The Republic of Gran Colombia under President Simón Bolívar (1819 - 1828) expands over South America\n***Mexico (1821)\n***Brazil (1822)\n*The United Provinces of Central America were formed in 1823. World Leaders\n* Emperor Francis II (Austria)\n* Chancellor Klemens Wenzel von Metternich (Austria)\n* King Louis XVIII (France)\n* King Charles X (France)\n* Pope Pius VII\n* Pope Leo XII\n* Emperor Alexander I (Russia)\n* Emperor Nicholas I (Russia)\n* King George IV (United Kingdom)\n* President James Monroe (United States)\n* President John Quincy Adams (United States) \n\n\n\n\n\n\n\n\n\n\n\n\n\n