1820 CE

German-Russian explorer Fabian Gottlieb von Bellingshausen discovers the continent of Antarctica during the First Russian Antarctic Expedition. A Constitutionalist insurrection breaks out at Oporto, Portugal. After the sinking of the American 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 cannibalism to allow some to survive.

In the 1820s, the 19th century.

Geopolitics & Diplomacy

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 Spain.source
January 8 – The General Maritime Treaty of 1820 is signed between the sheikhs of Abu Dhabi, Sharjah, Ajman, Umm al-Quwain and Ras Al Khaimah (later constituents of the Trucial States) in the Arabian Peninsula and the United Kingdom.source
January 29 – King George IV becomes the new British monarch upon the death his father George III after 59+ years on the throne. The elder George's death ends the 9-year period known as the British Regency.source
February 6 – Capture of Valdivia: Lord Cochrane occupies Valdivia in the name of the Republic of Chile.source
March 3 and 6 – The Missouri Compromise becomes law, allowing admission of Missouri and Maine, as slave and free states respectively, as U.S. states.source
March 9 – King Ferdinand VII of Spain accepts the new constitution, beginning the Trienio Liberal.source
March 15 – Maine is admitted as the 23rd U.S. state.source
March 15 – Maine is admitted as the 23rd U.S. state (see History of Maine).United States source
April 1 — Benjamin Chew Wilcocks becomes Consul of the United States at the Port of CantonChina source
8 June – Constitution of the German ConfederationGermany source
June 10 – Sir Thomas Munro is appointed as the British colonial Governor of the Madras Presidency, which encompasses most of southern India.India source
June 12 – Delegates in 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'."source
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.source
28 September – Establishment of a unified provisional juntaPortugal source
October 9 – Guayaquil declares independence from Spain.source
October 25–November 20 – The Congress of Troppau is convened between the rulers of Russia, Austria and Prussia.source
1 December – Campbelltown, New South Wales is established.Australia source
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.source
After the Liberal Revolution of 1820, the Portuguese court returns from Brazil to Portugal.Brazil source
The settlement of Worcester is established.South Africa source

Conflict & Security

22 January – Battle of TacuarembóPortugal source
February 13 – The Assassination of the Duke of Berry takes place in Paris. The Duke of Berry, nephew of Louis XVIII, is stabbed to death while attending the Paris Opera.source
February 14 – Emperor Minh Mạng starts to rule in Vietnam.source
February 20 – A revolt begins against the Spanish crown in Santa María Chiquimula (now in Guatemala).source
February 23 – The Cato Street Conspiracy, a plot to assassinate Britain's Prime Minister, Lord Liverpool, and his Cabinet is thwarted when police in London arrest 13 plotters after being warned by an informant.source
3-4 February - Capture of ValdiviaChile source
13 March – Clan Grant raid on Elgin in a disputed election to the town council.Scotland source
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.source
April 1 – A proclamation, signed "By order of the Committee of Organisation for forming a Provisional Government", begins the "Radical War" in Scotland.source
April 12 – Alexander Ypsilantis becomes the leader of Filiki Eteria, a secret organization to overthrow Ottoman rule over Greece.source
1 May – The Cato Street conspirators are the last to suffer judicial decapitation in the UK following their public hanging for treason outside Newgate Prison in London (legally, a mitigation of the last sentence in Britain of hanging, drawing and quartering).United Kingdom source
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 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.source
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.source
August 24 – A Constitutionalist insurrection breaks out at Oporto, Portugal.source
24 August – Military revolt in PortoPortugal source
September 2 – The Daoguang Emperor succeeds to the throne of Qing dynasty China.source
September 5 – José Gervasio Artigas flees to Paraguay.source
September 15 – Revolution breaks out in Lisbon against John VI of Portugal.source
26 September - Battle of TarpellancaChile source
Waikato and Ngāti Maniapoto defeat Ngāti Toa in two battles near at Kāwhia Harbour. After a siege at the harbour Ngāti Toa agree to cede their land and move south. Te Wherowhero is one of the leaders of Waikato, Te Rauparaha and Te Pēhi Kupe lead Ngāti Toa.New Zealand source
King Moshoeshoe moves the Basotho capital to Butha Buthe Mountain to escape conflict.South Africa source

Exploration & Expansion

January 27 (NS, January 15 OS) – An Imperial Russian Navy expedition, led by Fabian Gottlieb von Bellingshausen in Vostok with Mikhail Petrovich Lazarev, sights the Antarctic ice sheet.source
28 January – German-Russian explorer Fabian Gottlieb von Bellingshausen discovers the continent of Antarctica during the First Russian Antarctic ExpeditionGermany source
January 30 – British Royal Navy captain Edward Bransfield, an Irishman, becomes the first person to positively identify Antarctica as a land mass.source
30 January – Royal Navy captain Edward Bransfield in the Williams is the first person to positively identify Antarctica as a land mass.United Kingdom source
February 6 – 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".source
February 6 – 86 free African American colonists sail from New York City to Freetown, Sierra Leone.United States source
27 February – Samuel Marsden arrives on his third visit to New Zealand aboard HMS Dromedary. He unsuccessfully attempts to dissuade Thomas Kendall from his impending visit to England. The Dromedary spends 5-month getting timber in Whangaroa Harbour.New Zealand source
17 March - The first British settlers arrive in Table Bay, Cape Town on the "Nautilus" and the "Chapman".South Africa source
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.source
May 20 – At age 14, John Stuart Mill sets out on his formative trip to the south of France, staying with Samuel Bentham.source
19 August – Joseph Wild discovers Lake George and names the Snowy Mountains.Australia source
20 August - The Freedom Expedition of Perú sails for Paracas.Chile source
November 17 – American seal hunter Captain Nathaniel Palmer becomes the third known explorer to sight Antarctica. The Palmer Peninsula is later named after him.source
Creation of the municipality of Prescott and Russell in Upper Canada (today Ontario).Canada source

Religion & Belief

3 May – John Joseph Therry and Philip Conolly, the first Catholic priests officially appointed to Australia, arrive at Port Jackson from Ireland.Australia source
3 June – the Roman Catholic Cathedral of St Mary and St Anne in Cork is largely destroyed by arson.Ireland source
12 November – Kendall is ordained as a priest by Bowyer Sparke, Bishop of Ely.New Zealand source
The oldest known text containing Atla saga Ótryggssonar, one of the sagas of Icelanders, was written.Iceland source
The United Secession Church is established as a Presbyterian denomination by union of various churches which have seceded from the established Church of Scotland.Scotland source
David Wilkie paints Reading the Will.Scotland source
William Probert - Y Gododdin (first English translation)Wales source
John Scandrett Harford meets Bishop Thomas Burgess and offers to donate the site of Lampeter Castle for the construction of St David's College.Wales source

Economy & Finance

1 May – Sparekassen for Kjøbenhavn og Omegn is established in Copenhagen.Denmark source
6 May – failure of Newport's Bank in Waterford.Ireland source
25 May – failure of Roche's Bank and stoppage of Leslie's Bank in Cork.Ireland source
Anchor coinage is first struck in silver in London denominated in fractions of the Mauritian dollar for use in British colonies.source
National income - ₹11,684 millionIndia source
John Walker sets up as a grocer and wine and spirits merchant in Kilmarnock, from where he will sell the blended Scotch whisky which will be branded as Johnnie Walker.Scotland source

Technology & Infrastructure

3 May – A plough is used for the first time in New Zealand when John Gare Butler drives a team of six bullocks at Kerikeri.New Zealand source
July 26 – Union Chain Bridge opens across the River Tweed, between England and Scotland. Its span of 449 ft (137 m) is the world's longest for a vehicular bridge at this time.source
26 July – opening of Union Chain Bridge across the River Tweed between England and Scotland, designed by Captain Samuel Brown. Its span of 449 ft (137 metres) is the longest in the Western world at this time, and it is the first wrought iron vehicular suspension bridge of its type in Britain.Scotland source
August 1 — The Regent's Canal through to the London Docks is opened.source
1 August – Completion and opening of the Regent's Canal through to the London Docks.United Kingdom source
28 October – Governor Macquarie names Lake George after King George III.Australia source
22 November – Instruções, first election lawPortugal source
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.source
Suspension of construction of the Wellington Testimonial, Dublin, in Phoenix Park to the design of Robert Smirke.Ireland source
Charlottesville Woolen Mills built along the Rivanna RiverUnited States source
Crawshay Bailey becomes a partner at Nant-y-glo ironworks with his brother, Joseph Bailey.Wales source

Science & Discovery

March 10 – The Astronomical Society of London is founded.source
10 March – Astronomical Society of London is founded.United Kingdom source
April 8 – The statue of the Venus de Milo (Aphrodite of Milos, c. 150 BC-125 BC) is discovered on the Greek island of Milos, by a peasant named Yorgos Kentrotas.source
April 21 – Hans Christian Ørsted discovers the relationship between electricity and magnetism.source
11 May – Launch of HMS Beagle, the ship that will take the young Charles Darwin on his scientific voyage, at Woolwich Dockyard.United Kingdom source
5 December – Marsden leaves at the end of his third visit.New Zealand source
15 December – PS Comet (1812) is wrecked near Craignish.Scotland source
Divorce Bills Evidence Act (British statute)India source
Regina Maria Roche publishes The Munster Cottage Boy: a Tale.Ireland source
Robert Chambers's publishing company publishes The Songs of Robert Burns.Scotland source
Edward Jones – Hen Ganiadau CymruWales source

Health & Medicine

1 May – Robert Owen's Report to the County of Lanark, of a plan for relieving public distress and removing discontent (published 1821) is delivered.Scotland source
5 July – Pains and Penalties Bill put before Parliament to deprive Caroline of Brunswick, George IV's estranged wife, of the title of Queen Consort, leading to her de facto public trial before the House of Lords opening on 17 August. Although narrowly passed on 10 November in the House of Lords, the bill is withdrawn in the knowledge that it would almost certainly not pass the House of Commons.United Kingdom source
August 7 – The 1820 United States census is conducted, eventually determining a population of 11,176,475.United States source
Sheep population in Australia - 120,000.Australia source
The Edinburgh botanical garden is moved to the Inverleith site of the modern-day Royal Botanic Garden Edinburgh.Scotland source
AmaMfengu refugees flee to the Eastern Cape.South Africa source

Crime & Justice

23 February – A plot to murder the Cabinet, the Cato Street Conspiracy, is exposed. Bow Street Runners arrest conspirators in Paddington. Richard Smithers, a constable, is killed in the struggle.United Kingdom source
May 1 – The last judicial decapitation in the United Kingdom is meted out to the principals in the 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 "hanging, drawing and quartering".source
10 October – thief David Haggart murders the keeper of the Dumfries tolbooth while escaping imprisonment.Scotland source
18,957 black slaves leave Luanda, Angola.source
Bella and Hanna. The Eldest Daughters of M. L. Nathanson is painted by Christoffer Wilhelm EckersbergDenmark source
Robert Jones – Drych yr AmseroeddWales source

Disasters & Accidents

March 3 – A fire in Guangzhou in China burns 15,000 houses and kills an undetermined number of people.source
31 July – A fire breaks out in the wine depot at the Bercy section of Paris. It is reported later that "In the absence of water to supply the engines, an attempt was made to extinguish the flames with wine— of which a lake of 50 ft. square and more than a foot deep was formed; but the fire continued to rage, as well it might, being supplied by alcohol, and great destruction of property resulted.France source
November 20 – After the sinking of the American 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 cannibalism to allow some to survive.source
The first "colliery school" in the South Wales coalfield is established at Hirwaun.Wales source

Climate & Environment

Mount Rainier erupts over modern-day Seattle.source

Culture & Society

29 January – The Prince of Wales becomes King George IV of the United Kingdom upon the death of his father, King George III.Wales source
2 March – Kendall, Hongi Hika, and Hongi's nephew Waikato from Rangihoua, sail for England in the whaler New Zealander 1808 ship. Kendall confers with Professor Samuel Lee at Cambridge on the publication of Grammar and Vocabulary of the New Zealand Language. The book is published at the end of the year. The well known painting of Kendall with the two chiefs is painted by James Barry. Hongi's main purpose in this trip is to obtain muskets, at which he is eventually successful.New Zealand source
March 3 & 6 – Slavery in the United States: The Missouri Compromise becomes law.United States source
March 26 – Joseph Smith, founder of the Latter Day Saint movement, receives his First Vision in Palmyra, New York.source
April 15 – King William I of Württemberg marries his cousin, Pauline Therese, in Stuttgart.source
15 April – King William I of Württemberg marries his cousin, Pauline Therese, in Stuttgart.Germany source
22 April – Walter Scott is created 1st baronet of Abbotsford in the County of Roxburgh in the Baronetage of the United Kingdom.Scotland source
June 5 – Caroline of Brunswick, the estranged wife of King George IV, 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.source
June 18 – The Governor, Earl of Dalhousie, arrives.Canada source
July 20 – Saint Cronan's Boys' National School opens in Bray, County Wicklow, Ireland under the title Bray Male School. Its notable pupils will include President of Ireland Cearbhall Ó Dálaigh.source
The song Sønner av Norge is written by Henrik Anker Bjerregaard and Christian Blom.Norway source
James Read produces the first SeTswana book.South Africa source

Births

January 10 – Louisa Lane Drew, actress, prominent theater manager, grandmother of the Barrymores (died 1897)source
January 17 – Anne Brontë, English author (died 1849)source
February 8 – William Tecumseh Sherman, American Civil War general (died 1891)source
February 15 – Susan B. Anthony, American suffragist (died 1906)source
February 28 – John Tenniel, English illustrator (died 1914)source
March 4 – Alexander Worthy Clerk, Jamaican Moravian teacher and missionary (died 1906)source
March 14 – Victor Emmanuel II of Italy (died 1878)source
April 27 – Herbert Spencer, English philosopher (died 1903)source
May 12 – Florence Nightingale, English nurse (died 1910)source
July 22 – Oliver Mowat, Canadian lawyer, politician (died 1903)source
July 23 – Julia Gardiner Tyler, First Lady of the United States (died 1889)source
15 August - Jacinto Chacón, deputy for Santiago (died 1893)Chile source
September 17 – Earl van Dorn, American Confederate general (died 1863)source
October 6 – Jenny Lind, Swedish soprano (died 1887)source
November 28 – Friedrich Engels, German social philosopher (died 1895)source
29 November – Ferdinand Ludwig Herff, German-American physician (died 1912)Germany source
? – Báb, founder of Bábism and, according to the Baháʼís, predecessor of Baháʼu'lláh.Iran source
Sandile kaNgqika, a Xhosa nation (Rarabe) chief born in the Ciskei regionSouth Africa source

Deaths

January 23 – Prince Edward, Duke of Kent and Strathearn, member of British Royal Family and father of Queen Victoria (born 1767)source
January 29 – King George III of the United Kingdom (born 1738)source
February 5 – William Drennan, Irish physician, poet and radical politician (born 1754)source
March 11 – Benjamin West, Anglo-American painter of historical scenes (born 1738)source
March 22 – Stephen Decatur, American sailor (born 1779)source
June 6 – Henry Grattan, Irish politician (born 1746)source
June 19 – Sir Joseph Banks, English naturalist and botanist (born 1743)source
19 June (in England): Joseph Banks, naturalist on Cook's first voyage.New Zealand source
June 20 – Manuel Belgrano, Argentine politician, general in the Independence War (born 1770)source
September 3 – Benjamin Latrobe, Anglo-American architect (born 1764)source
September 16 – Nguyễn Du, Vietnamese poet (born 1766)source
September 26 – Daniel Boone, American pioneer (born 1734)source
28 September - Pedro Andrés del Alcázar (born 1752)Chile source
September — Jiaqing Emperor died suddenly of unknown causes. Mianning inherited the throne at the age of 38, becoming the Daoguang Emperor. He became the first Qing emperor who was the eldest legitimate son of his fatherChina source
October 8 – Henri Christophe, Haitian revolutionary leader (suicide) (born 1767)source
December 25 – Joseph Fouché, French statesman (born 1759)source
December 29 – Princess Pauline of Anhalt-Bernburg, German regent and social reformer (born 1769)source
29 December – Princess Pauline of Anhalt-Bernburg, German regent and social reformer (born 1769)Germany source