Christians did not invent the Christmas tree. Nor did they invent the use of holly and mistletoe. In fact, the only reason we celebrate Christmas when we do is because it coincided with the pagan celebration of the winter solstice. There is no way that Jesus was born on December 25th. According to the bible, he was born sometime in the spring, not winter.
Throughout Christian history, the use of the Christmas tree has been very controversial because it was taken from the pagans and was even banned by early Christians. The tradition of bringing evergreens into the home over the winter solstice dates back the the Egyptians and the practice was even condemned in the old testament:
Jeremiah 10:2-4: "Thus saith the LORD, Learn not the way of the heathen, and be not dismayed at the signs of heaven; for the heathen are dismayed at them. For the customs of the people are vain: for one cutteth a tree out of the forest, the work of the hands of the workman, with the axe. They deck it with silver and with gold; they fasten it with nails and with hammers, that it move not."
The first use of a fir tree was done by the heathen Greeks to worship the god Adonia, who allegedly was brought back to life by the serpent Aessulapius after having been slain.
The Romans also used evergreens in their own pagan traditions with a feast called Saturnalia in honor of Saturnus, the god of agriculture. They decorated their houses with greens and lights and exchanged gifts. They gave coins for prosperity, pastries for happiness, and lamps to light one's journey through life.
The Druids of England used fir trees during their winter solstice rituals
and used holly and mistletoe as symbols of eternal life because they were able to stay 'alive' during the winter when other trees became barren. They also placed wreaths of evergreen branches over doors to keep out evil spirits.
The Druids of Scandinavia tied fruit and candles to fir trees to celebrate their god, Woden (where the name Wednesday comes from) and also used the yule log (another pagan tradition) to celebrate the rebirth of the world on the shortest day of the year.
In early American history, pilgrims banned the use of Christmas trees because it was a mockery of Christianity to use pagan traditions to celebrate the birth of Jesus. In Puritan England, the use of holly and mistletoe were decried as well as the Christmas trees as anti-Christian.
So, go forth and put up a Christmas tree in your home to celebrate a merry Christmas, but please stop complaining about Christmas trees being stolen from us when it was never our tradition to begin with. If anything, it is the pagans who can claim that the 'holiday' has been taken out of the 'holiday tree' by Christians.