There’s a lot of discourse around this every year, and many of the assumptions people have about the origins of Christmas and many Christmas traditions are either flat-out untrue or have no evidence behind them, and others have truth in them but are misleading.

First is the claim that the date of Christmas is pagan in origin, that it was a co-opting of a Roman pagan holiday. This claim was made up in the 20th Century when people noticed that a) there were actually two different Roman holidays that overlapped with December 25th (Saturnalia and the Feast of the Unconquered Sun) and b) the accounts of feasting and partying for Saturnalia (we don’t have good records about the Feast of the Unconquered Sun, it was from one of the secretive mystery cults) sound a lot like the feasting and partying we do today for Christmas. There’s no evidence for this claim beyond “this sounds like it would make sense.” And there are significant problems with it.

Christmas was the last of the major holidays to be added to the Christian calendar, in the 4th Century BC; it’s not in the New Testament (unlike Easter and Pentecost, the two most theologically important holy days in the Christian calendar). We have the contemporary account of how they chose the date, which is not about pagan holidays but rather about numerology. They might have been lying, of course; but just because ancient numerology doesn’t make sense to modern people that doesn’t mean that they were lying about it. If you’re curious, here’s the story of how the calculations were made: at that time, they believed that Jesus had died on March 25. Jesus was perfect, therefore Jesus must have had a perfect life in numerological terms as well as everything else, therefore he must have died on the anniversary of his conception. (This is why Catholics celebrate the Annunciation–the day the angel came to Mary–as March 25th.) If Jesus was conceived on March 25th and had a perfect nine-month pregnancy, that puts his birth at December 25th.

As for the partying, Christmas was a time of fasting in the early church, not a time of partying. Solemn prayer and hymn-singing. No meat. Long worship services. If the date was chosen in relation to either Saturnalia or the Feast of the Unconquered Sun, the purpose was not to co-opt the pagan partying and say “hey, you can still have your midwinter parties in the Christian church!” but rather to contrast the drunken debauchery of the pagans with the sober piety of the Christians.

Christmas just wasn’t that important a date until Christianity started moving north (it shared prominence with Epiphany in the middle of winter, and was much less important than Easter). Up north, where the days are very short and everything is cold and dark, celebrating something in the middle of winter is very important to keep spirits up. And yes, the Germanic tribes and the Nordic peoples and the Slavs all had major festivals in midwinter, and many of the traditions associated with those festivals got attached to Christmas. (Trees, burning the Yule log, etc., etc.) But even up in the North where Christmas was much more important than it was in southern Europe, Christmas didn’t become The Biggest Celebration Of The Christian Year until the Victorians in the 19th Century.

Back to those pagan Germanic customs. Christian missionaries did not take those elements and incorporate them into Christmas celebrations. In fact, Christian missionaries and priests spent centuries trying to stamp those pagan elements out! They spent centuries telling people they were going to hell for still practicing paganism if they celebrated Christmas in a pagan way. For every priest who accepted or encouraged those pagan traditions, there were ten more trying diligently to stamp them out. Until eventually they gave up.