In the December 21, 2002 issue of World magazine, Gene Veith points out, "Critics of Christmas say that the Christian holiday is nothing more than the old pagan celebration of the winter solstice. . . . For the ancient pagans, the winter solstice meant the triumph of darkness. The Druids called it the "Death of the Sun." The fear was that the light would never return, unless human beings brought back the light with rituals and sacrifices. After the solstice, of course, the days started to grow longer, which was a big relief and reason for feasting and celebration.

"But whereas the pagans observed the solstice in terror, feverishly keeping the fires going lest the darkness overcome them, Christians turned what was literally the dead of winter into the happiest time of the year. The time of year now meant that when darkness is at its greatest, the light of God — Jesus Christ — is born. Gradually, though the night is still longer than the day throughout the winter, the light increases every day. Finally, the light surpasses the darkness. This occurs just after the spring equinox, March 21, another favorite time for holidays in the world's religions. Around that time Christians celebrate Easter, the day Christ rose from the dead, marking His victory over sin, death, the devil, and every darkness.

"In their seasonal symbolism of light and darkness, Christmas and Easter go together. Christmas marks the beginning of the light, and Easter marks the triumph of the light, just as the birth of the Christ child marks the beginning of His work, which culminates in the victory of His death and resurrection."

(You can read Veith's entire article at http://www.worldmag.com/world/issue/12-21-02/cultural_1.asp)