Twelfth Night is a holiday on January 5 that marks the 12th and final night of the Christmas season. Twelfth Night is the eve before the twelfth day of Christmas or the Epiphany celebration, which commemorates the adoration of the Magi before the infant Jesus.

In Tudor England, the Twelfth Night marked the end of a winter festival that started on All Hallows Eve--which we now celebrate as Halloween. A King or Lord of Misrule would be appointed to run the Christmas festivities, and the Twelfth Night was the end of his period of rule. The common theme was that the normal order of things was reversed. This Lord of Misrule tradition can be traced back to pre-Christian European festivals such as the Celtic festival of Samhain and the Ancient Roman festival of Saturnalia.

After Twelfth Night the Carnival season starts, which lasts through Mardi Gras. In some places such as New Orleans, Louisiana, the night of January 6 with the first Carnival celebrations is called Twelfth Night.