Editing 1820 (section)

== Events ==

=== January–March ===
*[[January 1]] – A constitutionalist military insurrection at [[Cádiz]] leads to the summoning of the Spanish Parliament to meet on March 7, becoming the nominal beginning of the "[[Trienio Liberal]]" in [[History of Spain (1814–73)|Spain]].<ref>{{cite book|author=Miguel A López-Morell|title=The House of Rothschild in Spain, 1812–1941|url=https://books.google.com/books?id=XOYFgUAxnkIC&pg=PT46|date=28 June 2013|publisher=Ashgate Publishing, Ltd.|isbn=978-1-4724-0424-4|pages=46}}</ref>
*[[January 8]] – The [[General Maritime Treaty of 1820]], officially the "General Treaty for the Cessation of Plunder and Piracy by Land and Sea, dated February 5, 1820") is signed between the sheikhs of [[Abu Dhabi]], [[Sharjah (emirate)|Sharjah]], [[Ajman]], [[Umm al-Quwain]] and [[Ras Al Khaimah]] (later constituents of the [[Trucial States]]) in the [[Arabian Peninsula]] and the United Kingdom.<ref>{{Cite book|last=Lorimer|first=John|title=Gazetteer of the Persian Gulf|publisher=British Government|location=Bombay|year=1915}}</ref>
*[[January 27]] ([[Old Style and New Style dates|NS]], January 15 OS) – An [[Imperial Russian Navy]] expedition, led by [[Fabian Gottlieb von Bellingshausen]] in ''[[Vostok (sloop-of-war)|Vostok]]'' with [[Mikhail Petrovich Lazarev]], sights the [[Antarctic ice sheet]].<ref name=Jones>{{cite book|first=A. G. E.|last=Jones|year=1982|title=Antarctica Observed: who discovered the Antarctic Continent?|publisher=Caedmon of Whitby|isbn=0-905355-25-3}}</ref>
*[[January 29]] – [[George IV of the United Kingdom]] becomes the new British monarch upon the death his father [[George III of the United Kingdom|King George III]] after 59 years on the throne. The elder George's death ends the 9-year period known as the [[British Regency]]. 
*[[January 30]] – British [[Royal Navy]] captain [[Edward Bransfield]], an Irishman,  becomes the first person to positively identify [[Antarctica]] as a land mass.<ref name=Jones/>
*[[February 6]]
** [[Capture of Valdivia]]: [[Thomas Cochrane, 10th Earl of Dundonald|Lord Cochrane]] occupies [[Valdivia]] in the name of the Republic of [[Chile]].
** A group of 86 free [[African American]] colonists sail from New York City to [[Freetown, Sierra Leone]], with a goal of creating a home for freed American slaves, to be called "[[Liberia]]".
*[[February 14]] – Emperor [[Minh Mạng]] starts to rule in [[Vietnam]].
*[[February 20]] – A revolt begins against the Spanish crown in [[Santa María Chiquimula]] (now in [[Guatemala]]).<ref>{{cite book|author=William George Lovell|title=Conquest and Survival in Colonial Guatemala: A Historical Geography of the Cuchumatán Highlands, 1500-1821|url=https://books.google.com/books?id=05wSqQiu52MC&pg=PA116|year=2005|publisher=McGill-Queen's Press - MQUP|isbn=978-0-7735-2741-6|pages=116}}</ref>
*[[February 23]] – The [[Cato Street Conspiracy]], a plot to assassinate Britain's Prime Minister, [[Robert Jenkinson, 2nd Earl of Liverpool|Lord Liverpool]], and his [[Liverpool ministry|Cabinet]] is thwarted when police in [[London]] arrest 13 plotters after being warned by an informant.<ref name="Ewald1868">{{cite book|author=Alexander Charles Ewald|title=The Last Century of Universal History: A Reference Book, Containing an Annotated Table of Chronology, Lists of Contemporary Sovereigns, a Dictionary of Battles and Sieges, and Biographical Notes of Eminent In-dividuals. From 1767 to 1867|url=https://books.google.com/books?id=flkQAAAAYAAJ&pg=PA67|year=1868|publisher=F. Warne & Company|pages=67}}</ref>
*[[March 3]] – A fire in [[Guangzhou]] in China burns 15,000 houses and kills an undetermined number of people.<ref name=Fires>"Fires, Great", in ''The Insurance Cyclopeadia: Being an Historical Treasury of Events and Circumstances Connected with the Origin and Progress of Insurance'', Cornelius Walford, ed. (C. and E. Layton, 1876) pp69</ref>
*[[March 3]] and [[March 6|6]] – The [[Missouri Compromise]] becomes law, allowing admission of [[Missouri]] and [[Maine]], [[slave and free states]] respectively, as [[U.S. state]]s.
*[[March 9]] – King [[Ferdinand VII of Spain]] accepts the new constitution, beginning the ''[[Trienio Liberal]]''.
*[[March 10]] – The [[Royal Astronomical Society|Astronomical Society of London]] is founded.
*[[March 15]] – [[Maine]] is admitted as the 23rd [[U.S. state]].
*[[March 26]] – [[Joseph Smith]], founder of the [[Latter Day Saint movement]], receives his [[First Vision]] in [[Palmyra (town), New York|Palmyra, New York]].<ref>Lefgren, J. C. (October 2002). "Oh, How Lovely Was the Morning: Sun 26 Mar 1820?". ''Meridian Magazine''. (available at http://www.johnpratt.com/items/docs/lds/meridian/2002/vision.html)</ref>
*[[March 28]] – An attempted [[coup d'état]] against [[Paraguayan]] dictator [[José Gaspar Rodríguez de Francia]] fails after a plot by [[Fulgencio Yegros]] and [[Pedro Juan Caballero (politician)|Pedro Juan Caballero]].

=== April–June ===
*[[April 1]] – A proclamation, signed "By order of the Committee of Organisation for forming a Provisional Government", begins the "[[Radical War]]" in Scotland.
*[[April 8]] – The statue of the [[Venus de Milo]] (Aphrodite of Milos, {{Circa|150 BC}}-125 BC) is discovered on the Greek island of [[Milos]], by a peasant named Yorgos Kentrotas.<ref>{{cite book|title=School Arts|url=https://books.google.com/books?id=18oVAQAAIAAJ|year=1922|publisher=Davis Publications|page=444}}</ref>
*[[April 12]] – [[Alexander Ypsilantis]] becomes the leader of ''[[Filiki Eteria]]'', a secret organization to overthrow [[Ottoman Empire|Ottoman]] rule over Greece.
*[[April 15]] – King [[William I of Württemberg]] marries his cousin, [[Pauline Therese of Württemberg|Pauline Therese]], in Stuttgart.
* April – [[Hans Christian Ørsted]] discovers the relationship between [[electricity]] and [[magnetism]].
*[[May 1]] – The last judicial [[decapitation]] in the [[United Kingdom]] is meted out to the principals in the [[Cato Street Conspiracy|Cato Street conspirators]] after their public [[hanging]] for treason in London. Legally, the post-hanging beheading is a mitigation of the last sentence in Britain of "[[Hanged, drawn and quartered|hanging, drawing and quartering]]".<ref>{{cite book|last=Abbott|first=Geoffrey|title=Execution: a Guide to the Ultimate Penalty|publisher=Summersdale Publishers|location=Chichester|year=2005|orig-date=1994|isbn=978-1-84024-433-5|pages=161–2}}</ref>
*[[May 11]] – {{HMS|Beagle}}, the ship that will later take young [[Charles Darwin]] on his scientific voyage to examine the "origin of the species", is launched at [[Woolwich Dockyard]].
*[[May 20]] – At age 14, [[John Stuart Mill]] sets out on his formative trip to the south of France, staying with [[Samuel Bentham]].
*[[June 5]] – [[Caroline of Brunswick]], the estranged wife of King [[George IV of the United Kingdom]], returns to England after six years abroad in Italy, where she has been carrying on an affair. Since ascending the throne in January, the King had sought to receive his government's approval for a divorce.<ref>{{cite book|authorlink=Christopher Hibbert|first=Christopher|last=Hibbert|title=Wellington: A Personal History|publisher=Da Capo Press|year=1999|page=220}}</ref>
*[[June 12]] 
** [[Élie Decazes]], leader of the opposition in France's Chamber of Deputies, introduces the "Law of the Double Vote", a proposal to add to the existing legislators by creating 172 seats that would be "selected by special electoral colleges" made up of the wealthiest 25% of voters in each of France's departments.<ref>Munro Price, ''The Perilous Crown: France Between Revolutions, 1814-1848'' (Pan Macmillan, 2010) p108</ref>
** Delegates in [[St. Louis, Missouri|St. Louis]] in the [[Missouri Territory]] approve a proposed state constitution, proclaiming that they "do mutually agree to form and establish a free and independent republic, by the name of 'The State of Missouri'."<ref>"Missouri", in ''Constitutional Documents of the United States of America 1776-1860'', ed. by Horst Dippel (K. G. Saur, 2007) p221</ref>
*[[June 29]] –  The cause of action that will lead to the U.S. Supreme Court case known as ''[[The Antelope]]'' arises, when a U.S. Treasury [[Cutter (boat)|cutter]] captures a ship of the same name, which is transporting 281 Africans who had been captured as slaves, in violation of the U.S. law prohibiting the slave trade.<ref>"Antelope Case", by John T. Noonan, Jr., in ''Dictionary of Afro-American Slavery'',  (Greenwood, 1997) p66</ref>

=== July–September ===
*[[July 13]] – A revolt under [[Guglielmo Pepe]] forces [[Ferdinand I of the Two Sicilies]] to sign a constitution modeled on the [[Spanish Constitution of 1812]].<ref name="Ewald1868"/>
*[[July 20]] – [[Saint Cronan's Boys' National School]] opens in [[Bray, County Wicklow]], [[Republic of Ireland|Ireland]] under the title ''Bray Male School''. Its notable pupils will include [[President of Ireland]] [[Cearbhall Ó Dálaigh]].
*[[July 26]] – [[Union Bridge (Tweed)|Union Chain Bridge]] opens across the [[River Tweed]], between England and Scotland. Its span of 449&nbsp;ft (137 m) is the world's longest for a vehicular bridge at this time.<ref>{{cite book|url=https://archive.org/details/amemoirsuspensi01drewgoog|title=A Memoir of Suspension Bridges: Comprising The History Of Their Origin And Progress|chapter=Section III|last=Drewry|first=Charles Stewart|year=1832|publisher=Longman, Rees, Orme, Brown, Green & Longman|location=London|pages=[https://archive.org/details/amemoirsuspensi01drewgoog/page/n55 37]–41|access-date=August 16, 2011}}</ref>
*[[August 1]] — The [[Regent's Canal]] through to the [[London Docks]] is opened.
*[[August 24]] – A [[Constitutionalist]] insurrection breaks out at [[Porto|Oporto]], [[History of Portugal#Crises of the nineteenth century|Portugal]].
*[[September 2]] – The [[Daoguang Emperor]] succeeds to the throne of [[Qing dynasty]] China.
*[[September 5]] – [[José Gervasio Artigas]] flees to [[Paraguay]]. 
*[[September 15]] – Revolution breaks out in [[Lisbon]] against [[John VI of Portugal]].<ref>{{cite book |author1=[[Matthew Anthony Fitzsimons]] |url=https://books.google.com/books?id=h6IwAQAAIAAJ |title=The Catholic Church Today: Western Europe |author2=Jean Bécarud |publisher=University of Notre Dame Press |year=1969 |isbn=978-0-268-00307-4 |page=162}}</ref>
[[File:Chicago in 1820.jpg|thumb|right|[[Chicago]] in 1820]]

=== October–December ===
*[[October 9]] – [[Guayaquil]] [[history of Ecuador|declares independence]] from Spain.
*[[October 25]]–[[November 20]] – The [[Congress of Troppau]] is convened between the rulers of Russia, Austria and [[Prussia]].<ref>{{cite book|author=Paul W. Schroeder|title=Metternich's Diplomacy at its Zenith, 1820-1823: Austria and the Congresses of Troppau, Laibach, and Verona|url=https://books.google.com/books?id=GSbFDQAAQBAJ&pg=PA98|date=1 January 1962|publisher=University of Texas Press|isbn=978-0-292-75034-0|pages=98}}</ref>
*[[November 17]] – American [[seal hunter]] Captain [[Nathaniel Palmer]] becomes the third known explorer to sight Antarctica. The Palmer Peninsula is later named after him.<ref>{{cite book|title=Oversight Visit to the Southern Pacific Rim: Report to the Committee on Science, Space, and Technology, U.S. House of Representatives, One Hundred First Congress, Second Session|url=https://books.google.com/books?id=0R151CAlW20C&pg=PA11|year=1991|publisher=U.S. Government Printing Office|pages=11}}</ref>
*[[November 20]] – After the sinking of the American [[Essex (1799 whaleship)|whaleship ''Essex'']] of [[Nantucket]], by a [[sperm whale]] in the southern Pacific Ocean, the survivors are left afloat in three small whaleboats. They eventually resort, by common consent, to [[Human cannibalism|cannibalism]] to allow some to survive.
*[[December 3]] – [[James Monroe]] is re-elected, virtually unopposed, in the [[1820 United States presidential election]]. One elector, [[William Plumer]] of [[New Hampshire]], casts his vote for [[John Quincy Adams]] in order to protest the administration of Monroe and [[Daniel Tompkins]] while also establishing Adams as a contender for the election in 1824.<ref>Lynn W. Turner, “The Electoral Vote against Monroe in 1820-An American Legend,” ''The Mississippi Valley Historical Review'' 42, no. 2 (September 1955): 253-254, https://www.jstor.org/stable/1897643?seq=1.</ref>

=== Date unknown ===
* The [[Argentine Confederation]] ([[Argentina]]) formally claims the [[Falkland Islands]], which are without permanent population at this time.<ref>{{cite book|title=The South Atlantic Crisis: Background, Consequences, Documentation : August 1982|url=https://books.google.com/books?id=c27jAAAAMAAJ&pg=PP4|year=1982|publisher=U.S. Department of State, Bureau of Public Affairs, Office of Public Communication, Editorial Division|pages=4}}</ref>
* [[Mount Rainier]] erupts over modern-day [[Seattle]].
* 18,957 black slaves leave [[Luanda]], [[Angola]].
* Construction work is completed on the [[Citadelle Laferrière]] in [[Haiti]], the largest [[fortification]] in the [[Americas]], built on the orders of [[Henri Christophe]] to defend the country against potential French reoccupation.<ref>{{cite book|first=Michele|last=Wagner|title=Haiti|url=https://books.google.com/books?id=SWk1urXDuikC|year=2002|publisher=G. Stevens|isbn=978-0-8368-2351-6|page=53}}</ref>
* [[Anchor coinage]] is first struck in silver in London denominated in fractions of the [[Mauritian dollar]] for use in British colonies.