21 December 1239

Operatives of the British Special Boat Service boarded the container ship Grande Tema in the Thames Estuary to detain four stowaways who had threatened the crew.

Countries that were part of the Maya civilization celebrated the end-date of a 5,126-year-long cycle in the Mesoamerican Long Count calendar.

In accordance with the Oslo II Accord, Israeli troops withdrew from Bethlehem in preparation for the transfer of control to the Palestinian National Authority.

Mexico's Popocatépetl volcano, dormant for 47 years, began erupting, and is now one of the nation's most active volcanoes.

The world's heaviest aircraft, the Antonov An-225 Mriya, made its first flight.

A bomb on board Pan Am Flight 103 detonated over Lockerbie, Scotland, killing 270 people.

Apollo 8 launched from Kennedy Space Center in Florida on a trajectory to the Moon; its crew (pictured) became the first humans to visit another celestial body.

The United Nations adopted the International Convention on the Elimination of All Forms of Racial Discrimination, which 88 member states have since signed.

An attempt by Greek Cypriot police to search certain Turkish Cypriot women in Nicosia escalated into island-wide violence, leading to 538 deaths and the displacement of nearly 27,000 people.

Snow White and the Seven Dwarfs, the first full-length cel-animated feature in film history, premiered at the Carthay Circle Theatre in Los Angeles.

Lieutenant Kijé, the first film composition by Sergei Prokofiev (pictured), premiered.

Nepal and the United Kingdom signed the first treaty that defined the international status of Nepal as an independent and a sovereign nation.

Moscow's Cathedral of the Immaculate Conception was consecrated.

the fictional character of Nora Helmer is first portrayed by Betty Hennings (pictured) at a showing of A Doll's House at the Royal Danish Theatre.

HMS Challenger departed Portsmouth on a scientific expedition that laid the foundations of oceanography.

Settlers from the United States in Mexican Texas made the first attempt to secede from Mexico, establishing the short-lived Republic of Fredonia.

The Pilgrims aboard the Mayflower landed at present-day Plymouth, Massachusetts, to establish the Plymouth Colony.

Fourteen people are killed and 25 others injured during a mass shooting at Charles University in Prague, Czech Republic.

A great conjunction of Jupiter and Saturn occurs, with the two planets separated in the sky by 0.1 degrees. This is the closest conjunction between the two planets since 1623.

2012 phenomenon: Festivities are held in parts of Mesoamerica to commemorate the conclusion of b'ak'tun 13, a roughly 5,126-year-long cycle in the Mesoamerican Long Count Calendar whose passing many New Age spiritualists had earlier held to portend a variety of cataclysmic or transformative events.

Iraq War: A suicide bomber kills 22 at the forward operating base next to the main U.S. military airfield at Mosul, Iraq, the single deadliest suicide attack on American soldiers in Iraq.

The Spanish Civil Guard intercepts a van loaded with 950 kg of explosives that ETA intended to use to blow up Torre Picasso in Madrid, Spain.

Cubana de Aviación Flight 1216 overshoots the runway at La Aurora International Airport, killing 18.

The city of Bethlehem passes from Israeli to Palestinian control.