Epiphany, which is celebrated with festivities and gift exchanges, is often called Twelfth Night. Gift-giving, in some cultures, extends throughout the 12 days of Christmas; elsewhere, gift-giving is limited to January 5 or 6 (or December 24-25). In some traditions, Epiphany is celebrated as the Theophany, on January 19th. In Western churches, Epiphany celebrates the coming of the magi. Where Epiphany is celebrated as the Theophany, the event in the life of Jesus Christ that is commemorated is his baptism.
Epiphany as a liturgical event is first mentioned in A.D. 361 by Ammianus Marcellinus, XXI ii.