He returned to politics to oppose the pro-slavery Kansas – Nebraska Act ( 1854 ); this law repealed the slavery-restricting Missouri Compromise ( 1820 ).

Percy Bysshe Shelley composed a " Hymn of Apollo " ( 1820 ), and the god's instruction of the Muses formed the subject of Igor Stravinsky's Apollon musagète ( 1927 – 1928 ).

Causes include controversy over admitting Missouri as a slave state in 1820, the acquisition of Texas as a slave state in 1845 and the status of slavery in western territories won as a result of the Mexican – American War and the resulting Compromise of 1850.

* 1820 – Nadar, French photographer, caricaturist, journalist, novelist and balloonist ( d. 1910 )

* 1820 – Alexander Ypsilantis is declared leader of Filiki Eteria, a secret organization to overthrow Ottoman rule over Greece.

* 1820 – George Grove, English historian ( d. 1900 )

* 1820 – John Tyndall, British physicist ( d. 1893 )

* 1890 – David Wilber, American politician ( b. 1820 )

* 1751 – Wilhelmina of Prussia, Princess of Orange ( d. 1820 )

* 1820 – Constitutionalist insurrection at Oporto, Portugal.

* Alfonso Sanz y Martínez de Arizala ( 28 January 1880, Madrid – 1970 ), married in 1922 to María de Guadalupe de Limantour y Mariscal ( d. 1977, Marbella ), daughter of Julio de Limantour y Marquet ( 17 June 1863, Mexico City – 11 October 1909, Mexico City ) and wife Elena Mariscal y ..., paternal granddaughter of French Joseph Yves de Limantour y Rence de la Pagame ( 1812, Ploemeur – 1885, Mexico City ) and wife Adèle Marquet y Cabannes ( 1820, Bordeaux –?

* 1771 – Karl Philipp Fürst zu Schwarzenberg, Austrian field marshal ( d. 1820 )

* 1820 – Alexander Cartwright, American inventor of Baseball ( d. 1892 )

Anne Brontë (; 17 January 1820 – 28 May 1849 ) was a British novelist and poet, the youngest member of the Brontë literary family.

Four more children followed: Charlotte, ( 1816 – 1855 ), Patrick Branwell ( 1817 – 1848 ), Emily, ( 1818 – 1848 ) and Anne ( 1820 – 1849 ).

* 1899 – Joseph Wolf, German artist ( b. 1820 )

* Daniel Boone ( November 2, 1734 October 22 – September 26, 1820 ) was an American pioneer, explorer, and frontiersman whose frontier exploits made him one of the first folk heroes of the United States.

* 1820 – The Venus de Milo is discovered on the Aegean island of Melos.

* 1754 – Andrew Ellicott, American surveyor ( d. 1820 )

However, during negotiations with the Choctaw in 1820, Andrew Jackson ceded more of Arkansas Territory to the Choctaw than he realized, resulting in a bend in the border between Arkansas and Oklahoma at Ft. Smith, Arkansas.

Pickens County was established on December 20, 1820, and named for revolutionary war hero General Andrew Pickens of South Carolina.

The first recorded discovery of marble was in 1820 by Dr. Edward Gantt, a physician who had accompanied General Andrew Jackson through the area in 1814.

An 1820 portrait of Lord Jeffrey by Andrew Geddes

* 1820: Andrew Hardie and John Baird were hanged and beheaded at Stirling after being tried for their part in the Radical War in Scotland.

During negotiations with the Choctaw in 1820, however, Andrew Jackson unknowingly ceded more of Arkansas territory.

He was the only son of Sir Andrew Dick-Lauder, 6th Baronet, whom he succeeded in 1820.

* Andrew Gray ( surveyor ) ( 1820 – 1862 ), American surveyor

* Saint Andrew, abbot of Raphael ( Tobolsk ) ( 1820 )

* Andrew Hardie ( radical ), Scottish radical, executed for his part in Radical War of 1820

Andrew Ellicott ( January 24, 1754 – August 28, 1820 ) was a U. S. surveyor who helped map many of the territories west of the Appalachians, surveyed the boundaries of the District of Columbia, continued and completed Pierre ( Peter ) Charles L ' Enfant's work on the plan for Washington, D. C., and served as a teacher in survey methods for Meriwether Lewis.

* Andrew Ellicott ( surveyor ) ( 1754 – 1820 ), influential surveyor.

Within it stands the memorial to John Baird and Andrew Hardie, the leaders of the 1820 Radical War otherwise known as the 1820 Insurrection.

* March 7-Andrew Rainsford Wetmore, Premier of New Brunswick ( b. 1820 )

On the occasion of Edwin Wetmore ’ s 21st birthday ( 1823 ), parents William and Anne gave him a plot of land in the Village of Silver Lake, along an upscale suburban street, Kent Road, then it was the farm that helped sustain his family and in 1820, Edwin had already built a 2-story Connecticut style farmhouse on this property.

* 1820 – John William Dawson, Canadian geologist ( d. 1899 )

* April 19 – Oliver Mowat, Canadian politician ( b. 1820 )

* James William Cook ( 1820 – 1875 ), Canadian businessman and political figure

* Sir Oliver Mowat ( 1820 – 1903 ), also considered a Father of Canadian Confederation

The first Anglo-American expedition to come through the county was led by Stephen H. Long who mistook the Canadian River for the Red River, in August 1820.

Between 1810 and 1820, several French Canadian fur traders, including Lamar Andie, Jean Baptiste Recollect, and Pierre Constant had established fur trading posts around Muskegon Lake.

Sir Oliver Mowat, ( July 22, 1820 – 19 April 1903 ) was a Canadian politician, and the third Premier of Ontario from 1872 to 1896, making him the longest serving premier of that province and the 3rd longest in all of Canadian history.

The area was first settled in 1820 by French Canadian fur trader Étienne Augustin de Lamorandière and his Anishinaabe wife Josephte Saisaigonokwe, who established a trading post named Shebahonaning ( canoe passage ) at the townsite.

* James William Cook ( 1820 – 1875 ), Canadian businessman and political figure

Pierre-Joseph-Olivier Chauveau ( May 30, 1820 – April 4, 1890 ), born in Charlesbourg, near Quebec City, was the first Premier of the Canadian province of Quebec following the establishment of the Dominion of Canada in 1867.

* April 16-Joseph-Charles Taché, a Canadian noted for his contributions to many aspects of the fabric of Canada ( b. 1820 )

* John William Dawson ( 1820 – 1899 ), Canadian geologist and Principal of McGill University

* Sir John Rose, 1st Baronet ( 1820 – 1888 ), Canadian lawyer, politician, and public servant

In 1929 Muriel H. Wright wrote that the Canadian River was named about 1820 by French traders who noted another group of traders from Canada had camped on the river near its confluence with the Arkansas River.

By the Treaty of Doak's Stand in 1820, the Canadian River was made the northern boundary of the Choctaw Nation.

* Étienne Guy ( 1774 – 1820 ), Canadian surveyor and politician

Sir John Rose, 1st Baronet, GCMG, PC ( August 2, 1820 – August 24, 1888 ) was a Canadian politician.

* James McNabb ( c. 1776 – 1820 ), Upper Canadian businessman and political figure

* John K. Ryerson ( 1820 – 1890 ), Canadian merchant and politician

Luc Letellier de Saint-Just, ( May 12, 1820 – January 28, 1881 ) was a Canadian politician.

* James Fraser Forbes ( 1820 – 1887 ), Canadian Member of Parliament

* John Kean ( Canadian politician ) ( 1820 – 1892 ), politician from Ontario, Canada

* Julius Faucher ( June 13, 1820 in Berlin-June 12, 1878 in Rome ) was a German journalist and a significant advocate of * Narcisse Henri Édouard Faucher ( April 18, 1844 – April 1, 1897 ) was a Canadian author, journalist, army officer, and politician who published books under the name Faucher de Saint-Maurice.