O Tannenbaum, O Tannenbaum!

“Let them over whom the fires of hell are imminent affix to their posts laurels doomed presently to burn: to them the testimonies of darkness and the omens of their penalties are suitable. You are a light of the world, and a tree ever green. If you have renounced temples, make not your own gate a temple." Thus did the second-century theologian Tertullian condemn those Christians who celebrated the winter festivals or decorated their houses with laurel boughs in honor of the Roman emperor. The Romans decked their homes with evergreen branches during the New Year, and ancient inhabitants of northern Europe cut evergreen trees—ancient symbols of life in the midst of winter—and planted them in boxes inside. Many early Christians, like Tertullian, were hostile to such practices.

But by the early Middle Ages, a legend had begun to circulate that when Christ was born in the dead of winter every tree throughout the world miraculously shook off its ice and snow and produced new shoots of green. At the same time, Christian missionaries preaching to Germanic and Slavic peoples were taking a more lenient approach to cultural practices. These missionaries believed that the Incarnation proclaimed Christ's lordship over those natural symbols that had previously been used for the worship of pagan gods. Not only individual human beings, but cultures, symbols, and traditions could be converted.

Of course, this did not mean that the worship of pagan gods themselves was tolerated. According to one legend, the 8th-century missionary Boniface, after cutting down an oak tree sacred to the pagan god Thor (and used for human sacrifice), pointed to a nearby fir tree as a symbol of the love and mercy of God.

Not until the Renaissance are there clear records of trees being used as a symbol of Christmas—beginning in Latvia in 1510 and Strasbourg in 1521. Legend credits Martin Luther with inventing the Christmas tree, but the story has little historical basis. The most plausible theory behind the 16th-century appearance of Christmas trees links them to medieval mystery plays. These dramas began as part of the church's liturgy, but by the late Middle Ages, they were rowdy, imaginative performances dominated by laypeople and taking place in the open air. Mystery plays celebrating the Nativity were linked to the story of creation—in part because Christmas Eve was also considered the feast day of Adam and Eve. As part of the mystery play for that day, the Garden of Eden was symbolized by a "paradise tree" hung with fruit.

Mystery plays were banned in many places in the 16th century. It may be that people set up "paradise trees" in their homes to compensate for the public celebration they could no longer enjoy. The earliest Christmas trees (or evergreen branches) used in homes were referred to as "paradises." They were often hung with round pastry wafers symbolizing the Eucharist, which developed into the cookie ornaments decorating German Christmas trees today. Our first detailed description of such a tree dates from 1605.

The custom gained popularity throughout the 17th and 18th centuries, against the protests of some clergy. Lutheran minister Johann von Dannhauer, for instance, complained (like Tertullian) that the symbol distracted people from the true evergreen tree, Jesus Christ. But this did not stop many churches from setting up Christmas trees inside the sanctuary. Alongside the tree often stood wooden "pyramids"—stacks of shelves bearing candles, sometimes one for each family member. Eventually these pyramids of candles were placed on the tree.

The Christmas tree only became common in the English-speaking world in the 19th century, popularized in England by Queen Victoria and introduced in America by German-speaking immigrants. Today, Christmas trees serve as a bridge between the Christian meaning of the holiday and its often empty secular expressions.

Edwin Woodruff Tait is assistant professor of Bible and religion at Huntington College in Huntington, Indiana.