Everyone knows what day of the year we celebrate Christmas, but not many know the real reason why.
On December 25th, nine in 10 Americans will celebrate Christmas, but few understand why. Everyone knows the trappings associated with the holiday—Christmas trees, red and green ornaments, presents, etc.—but its origins are less familiar.
Although Christians celebrate the birth of Jesus on December 25th, his exact birthdate is unknown. In the first 300 or so years of Christianity, the celebration of the leader’s birth was usually lumped in with Epiphany (January 6), if it was even observed at all. According to Christianity Today, it was around the year 273 that the church considered commandeering the existing pagan festival of winter solstice as fitting time to honor the son of God. It helped that December 25th already hosted two debaucherous holidays: natalis solis invicti (the Roman "birth of the unconquered sun"), and the birthday of Mithras, the Iranian "Sun of Righteousness.” It was considered a way to teach the masses a lesson or two about sin and redemption.
Christmas wasn’t widely observed until after Emperor Constantine converted to Christianity and declared it the Roman empire's favored religion. Western Christians officially began celebrating December 25 as the birth of Jesus in 336 AD.
So there you have it!