Actually...December 25th was the church's chosen date somewhere along of the time of the Council of Nicea around 325 CE, (AD)...Constantine reasoned that it was easier to incorporate this as a date for Christmas since it would coincide with the ancient Roman 'Saturnalia' celebration festival of the rebirth of the sun and thus making it an easier transition for pagan Romans, when and if they converted to the so-called Christanity of that era.
Ps...Trust me when I tell you that this was nothing more than a political ploy on the Emperor's part in order to try to unify his Empire with its many diverse religious entities he was dealing with at that time.
Some historians argue It was the 3rd century while others argue it was the 4th century 'while other historians argue that the birth of Christ has always been celebrated for centuries before the 3rd century
Jesus is my higher power, I celebrate on Dec 25th