4 December

4 December was the date of the Karn Flame Festival, a winter celebration. (PROSE: Time Traveller's Diary)

In 1642, Cardinal Richelieu died in France. (AUDIO: The Church and the Crown)

In 1872, the Mary Celeste was found abandoned. (PROSE: The Chase)

In 1952, the Third Doctor and Sarah Jane continued their undercover operation to bust up Tommy Ramsey's mafia-esque grip on London and to ward off a Xhinn invasion. Ramsey, unable to let the Doctor get away with not paying for protection, torched the Time Lord's clock repair shop to set an example for other local business owners who refused to pay. (PROSE: Amorality Tale)

In 1981, the Jex arrived on Earth, taking shelter in California's San Joaquin Valley. (PROSE: The King of Terror)

According to a calendar on the Snowcap base, 4 December 1986 was a Thursday. (TV: The Tenth Planet)

In 1993, Cristián Alvarez wrote a note to the Seventh Doctor, entreating the Time Lord to come to Mexico City, and to "bring Bernice and Ace". Alvarez passed the note on to UNIT, who eventually got it to the Doctor, who then showed up in Mexico City early 1994. (PROSE: The Left-Handed Hummingbird)

Undated events
In Salzburg, an alien dressed as the Krampus was preparing to eat some children. After the Fifth Doctor failed to persuade him the Krampus was just a myth, the alien died in a fire accidentally started by local children. (PROSE: Do You Believe in the Krampus?)