winter solstice

BRUMALIA

The Brumalia was an ancient Roman festival honoring Saturn, Ops, and Bacchus. (It is possibly related to the ancient Greek Lenaia, held in honor of Dionysus.) The festival lasted thirty days and ended on December 25, the day designated on the old Julian calendar as the winter solstice. The name is derived from the Latin word bruma, meaning "shortest day," "cold weather," or even "winter solstice." It included drinking and merriment. According to Choricius of Gaza, Oration XIII, the festival was celebrated as late as the 6th century AD during the reign of Emperor Justinian I.

In the Byzantine era, the Brumalia was celebrated from November 24 until the Saturnalia, December 17, with each day of the event known by a letter of the Greek alphabet. On any given day, If your name began with a corresponding letter, your friends might have expected you to invite them to a dinner party on that day, probably featuring a slain pig.

December 25 was also considered to be the birthday of Sol Invictis, a Syrian deity whose cult was introduced by Aurelian in AD 273. The idea that Christians chose to celebrate the birth of Jesus on December 25 because this was the date of an already existing festival of Sol Invictus was expressed in an annotation to a manuscript of a work by 12th-century Syrian bishop Jacob Bar-Salibi, but the notion is generally refuted now.

Consult these resources for more information about the Brumalia.