When is Twelfth Night? And is it the same as the twelfth day of Christmas?
Long ago no one celebrated Christmas until actual Christmas Day and then they would celebrate it for 12 days (often giving one present each day for those 12 days). The last night (Jan 6th) was called 12th night and was the end of the Christmas Celebration. It is entirely up to you when to take your tree down. Many people do it on Jan. 1st. But if you want to take it down on 12th night that would be, as I said, Jan. 6th.