The ancient Druids believed that mistletoe could be a sign of great sacredness. The one which was growing on the oak was cut off with the golden sickle by specially initiated priests during a special ceremony. people in Celtic and Teutonic traditions believed that the mistletoe could perform miracles, heal and protect.
Very interesting that the myth about mistletoe exist in Scandinavian tradition despite the fact that the plant does not grow in most of the area. The story goes that Loki tricked the blind god Hodur into murdering his own twin brother Balder with an arrow made of mistletoe. The mistletoe was the only plant to which Balder was vulnerable. The Prose Edda tells us that “The second son of Odin is Baldur, and good things are to be said of him. He is best, and all praise him; he is so fair of feature and so bright, that light shines from him. A certain herb is so white that it is likened to Baldr’s brow; of all grasses, it is whitest, and by it, thou mayest judge his fairness, both in hair and in the body” (Brodeur’s translation)
Many pagan cultures regarded the white berries to be a symbol of male fertility because mistletoe seeds resembled semen. For example in Celtic tradition, it was a sperm of Taranis, a personification of thunder.
For Romans mistletoe was a symbol of peace and love, they believed that it can protect the home if hung over doorways. It is where the tradition of hanging the mistletoe comes from.