Events on December 6 43
Year 963
Pope Leo VIII is appointed to the office of Protonotary and begins his papacy as antipope of Rome.
Year 1240
Mongol invasion of Rus': Kiev under Daniel of Galicia and Voivode Dmytro falls to the Mongols under Batu Khan.
Year 1534
The city of Quito in Ecuador is founded by Spanish settlers led by Sebastián de Belalcázar.
Year 1648
Colonel Thomas Pride of the New Model Army purges the Long Parliament of MPs sympathetic to King Charles I of England, in order for the King's trial to go ahead; came to be known as "Pride's Purge".
Year 1704
Battle of Chamkaur (1704): During the Mughal-Sikh Wars, an outnumbered Sikh Khalsa defeats a Mughal army.
Year 1865
The Thirteenth Amendment to the United States Constitution is ratified, banning slavery.
Year 1904
Theodore Roosevelt articulated his "Corollary" to the Monroe Doctrine, stating that the U.S. would intervene in the Western Hemisphere should Latin American governments prove incapable or unstable.
Year 1917
Halifax Explosion: A munitions explosion near Halifax, Nova Scotia kills more than 1,900 people in the largest artificial explosion up to that time.
Year 1917
World War I: USS Jacob Jones is the first American destroyer to be sunk by enemy action when it is torpedoed by German submarine SM U-53.
Year 1921
The Anglo-Irish Treaty is signed in London by British and Irish representatives.
Year 1922
One year to the day after the signing of the Anglo-Irish Treaty, the Irish Free State comes into existence.
Year 1928
The government of Colombia sends military forces to suppress a month-long strike by United Fruit Company workers, resulting in an unknown number of deaths.
Year 1933
U.S. federal judge John M. Woolsey rules that James Joyce's novel Ulysses is not obscene.
Year 1941
World War II: The United Kingdom and Canada declare war on Finland in support of the Soviet Union during the Continuation War. Camp X opens in Canada to begin training Allied Secret Agents for the War.
Year 1956
A violent water polo match between Hungary and the USSR takes place during the 1956 Summer Olympics in Melbourne, against the backdrop of the Hungarian Revolution of 1956.
Year 1957
Project Vanguard: A launchpad explosion of Vanguard TV3 thwarts the first United States attempt to launch a satellite into Earth orbit.
Year 1967
Adrian Kantrowitz performs the first human heart transplant in the United States.
Year 1971
Pakistan severs diplomatic relations with India, initiating the Indo-Pakistani War of 1971.
Year 1973
The Twenty-fifth Amendment: The United States House of Representatives votes 387 to 35 to confirm Gerald Ford as Vice President of the United States. (On November 27, the Senate confirmed him 92 to 3.)
Year 1975
The Troubles: Fleeing from the police, a Provisional IRA unit takes a British couple hostage in their flat on Balcombe Street, London, beginning a six-day siege.
Year 1977
South Africa grants independence to Bophuthatswana, although it is not recognized by any other country.
Year 1982
The Troubles: The Irish National Liberation Army bombed a pub frequented by British soldiers in Ballykelly, Northern Ireland, killing eleven soldiers and six civilians.
Year 1989
The École Polytechnique massacre (or Montreal Massacre): Marc Lépine, an anti-feminist gunman, murders 14 young women at the École Polytechnique in Montreal.
Year 1991
In Croatia, forces of the Yugoslav People's Army (JNA) bombard Dubrovnik after laying siege to the city for seven months.
Year 1992
The Babri Masjid in Ayodhya, India, is demolished, leading to widespread riots causing the death of over 1,500 people.
Year 1997
A Russian Antonov An-124 Ruslan cargo plane crashes into an apartment complex near Irkutsk, Siberia, killing 67.
Year 2005
An Iranian Air Force C-130 military transport aircraft crashes into a ten-floor apartment building in a residential area of Tehran, killing all 84 on board and 44 more on the ground.
Year 2006
NASA reveals photographs taken by Mars Global Surveyor suggesting the presence of liquid water on Mars.
Year 2015
Venezuelan elections are held. For the first time in 17 years the United Socialist Party of Venezuela loses its majority in parliament.