Where did the custom of the Christmas tree come from?
The custom of the Christmas tree came from the Assyro-Babylonian system and found prominence in the festivals of the worship of Attis and also Adonis. Attis was a god as father and son in a modal structure that was crucified on a pine tree and the pine was sacred to him. It was cut and decorated each year and the decoration was kept and burnt the following year as a symbol of regeneration. The traditions are covered in the paper: The Origins of Christmas and Easter (No. 235).