The custom of a Christmas tree, undecorated, is believed to have begun in Germany, in the first half of the 8th century.

The earliest story relates how a British monk and missionary, St. Boniface, was preaching a sermon on the Nativity to a tribe of Germanic Druids outside the town of Geismar. To convince the druids that the oak tree was not sacred and inviolable, the "Apostle of Germany" felled one on the spot. Toppling, it crushed every shrub in its path except for a small fir sapling. A chance event can lend itself to numerous interpretations, and legend has it that Boniface, attempting to win converts, interpreted the fir's survival as a miracle, concluding, "Let this be called the tree of the Christ Child." Subsequent Christmases in Germany were celebrated by planting fir saplings.

The history of the modern Christmas tree goes back to 16th century Germany. In Alsace (Elsass), dated 1561, a law stated that "no burgher shall have for Christmas more than one bush of more than eight shoes' length." The decorations hung on a tree in that time, the earliest we have evidence of, were "roses cut of many-colored paper, apples, wafers, gilt, sugar." Around Strasbourg there was a widespread practice of bringing trees (evergreens, not necessarily a fir-tree) into houses for decoration during Christmastide.

The modern custom is also connected with the Paradise tree hung with apples, present in the medieval religious plays. The decorations could symbolize the Christian Hosts. Instead of trees, various wooden pyramidal structures were also used. In 17th century the Christmas tree spread through Germany and Scandinavia. Eventually the tree was extensively decorated, first with candles and candies, then with apples and confections, later with glittering mass-produced ornaments.

The success of Christmas tree in Protestant countries was enhanced by the legend which attributed the tradition to Martin Luther himself. It is a widely held belief that Martin Luther first added lighted candles to a tree. Walking toward his home one winter evening, composing a sermon, he was awed by the brilliance of stars twinkling amidst evergreens. To recapture the scene for his family, he erected a tree in the main room and wired its branches with lighted candles. In England the tradition was made popular by the German Prince Albert, husband of Queen Victoria. The German immigrants brought the Christmas tree to America in 17th century. Public outdoors Christmas trees with electric candles were introduced in Finland in 1906, and in USA (New York) in 1912. The claim of the Pennsylvania Germans to have initiated the Christmas tree custom in America is undisputed today. And it's in the diary of Matthew Zahm of Lancaster, Pennsylvania, under the date December 20, 1821, that the Christmas tree and its myriad decorations received their first mention in the New World.

It is no surprise that, like many other festive Christmas customs, the tree was adopted so late in America. To the New England Puritans, Christmas was sacred. The Pilgrims' second governor, William Bradford, wrote that he tried hard to stamp out "pagan mockery" of the observance, penalizing any frivolity. The influential Oliver Cromwell preached against "the heathen traditions" of Christmas carols, decorated trees and any joyful expression that desecrated "that sacred event."