The winter solstice ritual was called Lenaea, the Festival of the Wild Women. In very ancient times, a man representing the harvest god Dionysos was torn to pieces and eaten by a gang of women on this day. Later in the ritual, Dionysos would be reborn as a baby. By classical times, the human sacrifice had been replaced by the killing of a goat. The women’s role had changed to that of funeral mourners and observers of the birth.
Now that’s my kind of festival, except the human sacrifice part.