Historically, there has been opposition to the custom of the Christmas tree because of its pagan origins. In 1851, parishioners in Cleveland, Ohio, USA condemned as a pagan practice the actions of the pastor, Henry Schwan, for decorating one of the earliest Christmas trees in an American Christian church Robert Chambers, a Scottish author and publisher in his 1832 Book of Days asserts that the festivities of Christmas "originally derived from the Roman Saturnalia, had afterwards been intermingled with the ceremonies observed by the British Druids at the period of winter-solstice, and at a subsequent period became incorporated with the grim mythology of the ancient Saxons. Two popular observances belonging to Christmas are more especially derived from the worship of our pagan ancestors—the hanging up of the mistletoe and the burning of the Yule log." [2] 

They also decorated living trees with bits of metal and replicas of their God, Bacchus. Tertullian (circa 160 - 230), an early Christian leader and a prolific writer, complained that too many fellow-Christians had copied the Pagan practice of adorning their houses with lamps and with wreathes of laurel at Christmas time.[3]

Partly because of the Pagan origins of Christmas,  the early Puritans in the United States did not celebrate the holiday and tried to stamp it out whenver it began to surface. The English Puritans condemned a number of customs associated with Christmas, such as the use of the Yule log, holly, mistletoe, etc. Oliver Cromwell preached against "the heathen traditions" of Christmas carols, decorated trees and any joyful expression that desecrated "that sacred event."

In America, the Pilgrim's second governor, William Bradford, a Puritan, tried hard to stamp out all "pagan mockery" at Christmas time and Christmas trees were not used by Puritans in colonial times. The first Christmas tree in an American church seems to have been in 1851, Pastor Henry Schwan of Cleveland OH appears to have been the person responsible for decorating the first Christmas tree in an American church. His parishioners condemned the idea as a Pagan practice; some even threatened the pastor with harm. Eventually the Christmas tree became a standard part of secular Christianity.  

The Christmas tree itself is almost always an evergreen, usually a balsam or Douglas fir, decorated with lights and ornaments as part of the Christmas festivities, states the Encyclopedia Britannica. The use of evergreen trees, wreaths, and garlands as a symbol of eternal life was an ancient custom of the Egyptians, Chinese, and Hebrews.[3] It would appear that tree worship was common among the pagan Europeans, and it survived after their conversion of the masses to Christianity in  Scandinavian customs of decorating the house and barn with evergreens at the New Year to scare away the devil.  A tree for the birds during Christmastime was used, and the custom continued in Germany, with the  placing a Yule tree at an entrance or inside the house in the midwinter holidays.

            The modern Christmas tree, though, originated in western Germany. While there are many stories of how the Christmas tree became a permanent fixture in the Germanic custom, one of the ideas behind its popularity stems form a popular medieval play about Adam and Eve, the tree representing the “Paradise tree” of the Biblical story, representing the Garden of Eden. The Germans set up a Paradise  tree in their homes on December 24, the religious feast day of Adam and Eve.  In the same  room, during the Christmas season, was the Christmas pyramid, a triangular construction of wood, with shelves to hold Christmas figurines, decorated with evergreens, candles and a star.  By the 16^th Century, the Christmas pyramid and Paradise tree had merged, becoming the Christmas tree. [2]

            The custom was widespread among the German Lutherans by the 18^th century, but it was not until the following century that the Christmas tree became a deep-rooted German tradition. introduced into England in the early 19^th century, the Christmas tree was popularized in the mid-19^th century by the German Prince Albert, husband of Queen Victoria. Brought to North America by German settlers as early as the 17^th century, Christmas tress were the height of fashion by the 19^th century.  End of article. 

The celebration of Christmas itself is associated with, “ the pagan agricultural and solar observances at midwinter. It was a time of merrymaking and exchange of gifts. December 25 was also regarded as the birth date  of the Iranian mystery go Mithra, the Sun of righteousness.”

“Modern-day opposition continues: some condemn the Christmas tree because they believe it to be a Christian symbol; others condemn it because they believe -- incorrectly -- that the custom of cutting down a tree, erecting it in the home and decorating it is a Pagan custom,” states Religious Tolerance.org, while others view it as a “symbol of hope.” [1]

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References:

1. All About the Christmas Tree. Religious Tolerance.org. (Retrieved November 13, 2009). http://www.religioustolerance.org/xmas_tree.htm

2. Christmas Tree. Wikipedia.org. (Retrieved November 13, 2009. http://en.wikipedia.org/wiki/Christmas_tree

3. Christmas Tree, (1989). Encyclopedia Britannica Vol 3 p. 284