December 2: The Battle of the Ch'ongch'on River ends with the Chinese People's Volunteer Army expelling United Nations forces from North Korea.

December 2: The Eighth United States Army, under the command of General Walton Walker, began "the longest retreat in United States military history", destroying whatever equipment and supplies it could not take with it, as the American troops pulled back from Chinese troops advancing into North Korea.

December 2: The science fiction short story collection I, Robot by Isaac Asimov was published.

December 3: The Disenchanted by Budd Schulberg topped The New York Times Fiction Best Seller list.

December 4: Republican Congressman Richard Nixon took office as U.S. Senator from California following a bitter election campaign.

December 9: The catalytic converter for gasoline combustion engine automobiles was announced by French-born American mechanical engineer Eugene Houdry.

December 10: Bertrand Russell won the Nobel Prize in Literature "in recognition of his varied and significant writings in which he champions humanitarian ideals and freedom of thought".

December 10: Dr. Ralph Bunche receives the 1950 Nobel Peace Prize for his mediation in Palestine. The first non-white person to do so.

December 19: General Dwight D. Eisenhower, retired from the United States Army, was brought back into service by President Truman to serve as the first Supreme Allied Commander of Europe .

December 20: Sunset Boulevard was named Best Film at the 22nd National Board of Review Awards.

December 21: One of the most well-known articles of clothing in comic strips was introduced, when Charlie Brown was first seen in his "zig-zag T-shirt". Cartoonist Charles M. Schulz had added the distinction in order to set Charlie Brown apart from the rest of the strip's characters.

December 21: The comedy-drama film Harvey starring James Stewart and Josephine Hull was released in the United States.

December 22: Napalm was used for the first time in war in Vietnam, when High Commissioner de Lattre ordered the French Air Force to bomb a concentrated group of Viet Minh guerillas in the Tiên Yên District.

December 25: The Stone of Scone, the traditional coronation stone of Scottish monarchs, English monarchs and, more recently, British monarchs, was stolen from London's Westminster Abbey by a group of four Scottish students.

December 30: "The Tennessee Waltz" by Patti Page topped the Billboard Best Sellers in Stores chart. (source: Wikipedia)