Well, let's see, there's Christmas, Hanukkah, and Pancha Ganapati, among the more popular religions. And dozens more. Or we could go back to the core reason for most institutional celebrations about that time, and the only one with actual physical relevane: the winter solstice. The longest night of the year, and beginning of the return of the sun. Traditional time for all manner of celebrations of rebirth and new beginnings.
Most of what has become "the traditional Christmas celebration": santa, decorated trees, lots of lights, gifts, big meals, etc. have their roots in various pagan soltice celebrations in lands conquered by Christianity: the conquered aren't going to give up their soltice celebrations, so you'd best offer them an alternative so that they can party around your icons instead of their own. Only requires adjusting your calender a little bit...