Externsteine Relief - a Benedictine carving at once was the center of German pagan religion in the Teutoburger Wald. It portrays the cutting down of the 'Irminsul' and the rising in its place of the 'Evergreen' Cross of the Conquering Christ.
Originally uploaded by Aristibule.
This also produced the custom of the 'community Christmas tree' which is an 'outside' tree. The custom spread across the South from Williamsburg in the years before the War. Before the German Christmas tree (which might have been used in the Carolinas amongst the Germans since the early 1700's) there was already the custom of Christmas greenery in Southern households: though primarily Mistletoe and Holly.
Also, the origins with St. Boniface "When St. Boniface chopped down the pagan Thor's oak at Geismar, he claimed that the tiny fir tree growing in its roots as the new Christian symbol. He told the heathen tribes: "This humble tree's wood is used to build your homes - let Christ be at the center of your households. Its leaves remain evergreen in the darkest days - let Christ be your constant light. Its boughs reach out to embrace and its top points to heaven - let Christ be your comfort and your guide." So the fir tree became a sign of Christ among the German peoples, and eventually it became a world-wide symbol of Christmas."
One thing I plead of readers: the Christmas Tree is not an *Advent* custom. Traditionally (and still in Germanic Europe) one should put the tree up on Christmas Eve - as a surprise for the children on Christmas morning before leaving for the 'Christ Mass'. The tree is taken down at Epiphany/Theophany (after the 12 days of Christmas.) Also: St. Nicholas is a good traditional date for the giving of gifts: but it needn't be excessive, or a replacement for providing for family what one should normally provide.