I think that is is important to note that there is very little real evidence for Christmas being taken from saturnalia. You can google christmas and saturnalia and come up with plenty of web articles, but looking at the actual history of it makes it pretty clear. Christmas takes place around the same time of saturnalia, sure, but that does not make it a Christian stab at replacing it. Saturnalia was traditionally observed between the 17th and 23rd of December, not the 25th. It was a 5-7 day festival, not a one day festival. Additionally, the church is said to have gotten the 25th by taking the day John's father was told he would have a son (shortly after the day of attonement), the new testiment statement that Elizabeth was 6 months pregnant when Jesus was conceived, and adding 40 weeks to the end for the average pregnancy. This would put Jesus born in late December. This general time line was documented as being calculated as early as CE 200s.

They chose it to mess with the pagan Yule celebrations tho, and what the fuck is Saturnalia?