http://en.wikipedia.org/wiki/Christmas_Tree
Germanic tribes
Patron trees (for example, the Irminsul, Thor's Oak and the figurative Yggdrasil) held special significance for the ancient Germanic tribes, appearing throughout historic accounts as sacred symbols and objects. Among early Germanic tribes the Yule tradition was celebrated by sacrificing male animals and slaves by suspending them on the branches of trees.[citation needed]
According to Adam of Bremen, in Scandinavia the pagan kings sacrificed nine males of each species at the sacred groves every ninth year.[citation needed] According to one legend, Saint Boniface attempted to introduce the idea of trinity to the pagan tribes using the cone-shaped evergreen trees because of their triangular appearance.[citation needed]
Dionysus in his Triumphant Return; behind the god, Victoria holds an evergreen.The Christmas tree is often explained as a Christianization of the ancient pagan idea that the evergreen tree represents a celebration of the renewal of life.
Medieval
Medieval legends tended to concentrate more on the miraculous "flowering" of trees at Christmas time.[citation needed] A branch of flowering Glastonbury thorn is still sent annually for the Queen's Christmas table in the United Kingdom.
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