640 – Pope John IV is elected.
1294 – Pope Boniface VIII is elected, replacing St. Celestine V, who had resigned.
1777 – Kiritimati, also called Christmas Island, is discovered by James Cook.
1814 – Representatives of Britain and the United States sign the Treaty of Ghent, ending the War of 1812.
1818 – The first performance of “Silent Night” takes place in the church of St. Nikolaus in Oberndorf, Austria.
1826 – The Eggnog Riot at the United States Military Academy begins that night, wrapping up the following morning.
1851 – Library of Congress burns.
1865 – The Ku Klux Klan is formed.
1906 – Radio: Reginald Fessenden transmits the first radio broadcast; consisting of a poetry reading, a violin solo, and a speech.
1914 – World War I: The “Christmas truce” begins.
1924 – Albania becomes a republic.
1941 – World War II: Kuching is conquered by Japanese forces.
1941 – World War II: Benghazi is conquered by British forces.
1943 – World War II: U.S. General Dwight D. Eisenhower is named Supreme Allied Commander for the Invasion of Normandy.
1951 – Libya becomes independent from Italy. Idris I is proclaimed King of Libya.
1964 – Vietnam War: Viet Cong operatives bomb the Brinks Hotel in Saigon, South Vietnam to demonstrate they can strike an American installation in the heavily guarded capital.
1968 – Apollo program: The crew of Apollo 8 enters into orbit around the Moon, becoming the first humans to do so. They performed ten lunar orbits and broadcast live TV pictures.
1999 – Indian Airlines Flight 814 is hijacked in Indian airspace between Kathmandu, Nepal, and Delhi, India. The aircraft landed at Kandahar in Afghanistan. The incident ended on December 31 with the release of 190 survivors (one passenger is killed).