Jim,
I am far from an authority when it comes to religion but Christ was born late September, or early October. Larry is right, we do not know the exact date.
December 25th was selected as THE date to unify the factions in the early Roman church (between James, who wanted only Jews as converts to Christianity and Paul who, at the direction of Christ took the Gospel to the Gentiles) and bring into the fold those who were not even Christians but pagans.
These pagans loved to party so Dacember 25th became an all important party day.<g> However, it IS NOT the birth of Christ.

Sorry for getting carried away but I was forced to take 15 semester hours of Theology at Loyola (a forced minor). Something that is not done today! Funny how you remember information from those classes you hated the most.<VBG> Best, Jim