Well, that depends on who you ask. Read on, you might learn something:

Judaism, far older than Christianity, celebrates Chanukkah;
Hinduism, far older than Christianity, has Diwali, the celebration of lights;

In fact, find below quoted a rather interesting article about the various far-older-than-Christianity cultures celebrating the end of the year:

"YULE LORE

In keeping with the Yule season, this article will focus on some of the cultures that have contributed to our modern celebration of the winter solstice festival.

The modern Yule festival, of all our celebrations, has to contain the largest blend of celebrations of any Western festival. The practices and the date it is celebrated on, have been contributed by a mixture of cultures, including the Romans, the Celts, and Saxons, all of whom, from the northern latitudes of Europe to the Mediterranean area, celebrated the rebirth of the sun.

In addition to the state religion of Rome, other cults in the Roman world, such as Christianity, the worship of Mithras, and the worship of the sun (Sol Invictus - the Unconquerable Sun), celebrated a major festival at the end of December.

The Roman state religion called the winter solstice celebration "Saturnalia", a festival honouring the god Saturn. Originally, Saturnalia was held on only one day, December 17, but by the late republican period (circa 1st century BC), its observation extended over a number of days. Saturnalia was a festival of joy, optimism, and good will, just as it is for us. This is not at all surprising, as the Christian religion absorbed many of Saturnalia's festivities into the Christian celebration of the birth of Christ, since Saturnalia, being one of the most popular festivals of the whole year in the Roman world, proved to be impossible to eradicate.

Saturnalia began on December 17 with a religious ceremony at the temple of Saturn in the Forum, after which a free public banquet often followed. Stores and Business were closed so that all workers could enjoy the celebration, and people greeted each other in the streets with the salutation "Io Saturnalia" ("Hurrah, Saturnalia!"), the Roman equivalent of "Merry Christmas!"

Saturnalia was very much a time for family dinners, parties, and gift giving. It was a time to wish your friends and neighbours well. It was even a time slaves could enjoy, for at this time of year, the slaves became the masters for a day and were waited on by their owners. Some owners even gave their slaves gifts, and possibly even the day off! Even the emperor wore a freedman's cap (the cap a freed slave wore to show his status) at this time, possibly to show the equalized status of all men during the celebrations.

The Sabbat of Yule is a midwinter festival that was celebrated by the Celts on Dec 20-21, when the winter sun enters Capricorn. The name Yule comes from the Old Norse "iul," meaning 'wheel' and referring to the idea of the year as a wheel turning through the seasons. Among the Norse, too, Yule was a solstitial festival that celebrated the rebirth of the sun, or the rebirth of the Norse god Frey. The Celtic name for Yule was "Alban Arthan" and was for them, as it was for the Romans who celebrated Sol Invictus, a celebration of the day of the sun, once weakened, begins to strengthen again.

Traditional Celtic Yule celebrations include lighting fires, both inside and outside the house, and decorating the house with holly, ivy, mistletoe, bay, rosemary, and branches of box trees. The Yule log (oak, pine, ash, or birch) was associated both with the rebirth of the sun and with fertility rites, being used as a phallic symbol.

The Saxons celebrated Modranect on Dec 24-25. It was the night of Christmas Eve and means "the night of the Mother," or "of Mothering." This was a celebration of the birth of the sun at the winter solstice. The day following the Night of the Mother was devoted to the Goddess as Sea-Mother. At this time an image of the Goddess was launched out to sea. (An interesting aside to be considered here is that one of the titles of the Virgin Mary is "Stella Maris", or "Star of the Sea." This clearly connects the Virgin Mary, a figure only ostensibly secondary to the Christ Child, with the Mother Goddesses.)

The celebrations, symbols, and dates that the Christian Church incorporated into their religious repertoire suggests that the membership of the Church held on to their Pagan beliefs, using Christian dogma merely as a veneer to make their covert beliefs acceptable overtly. Given the fact that the early Christians truly believed that Jesus, as the sun of the Hebrew God, was resurrected after his crucifixion, it is possible that Jesus' birthday came to be celebrated on Dec 25, not so much as to incorporate an already well-established Pagan celebration, but more to identify him as the God (as the sun) reborn."