I think the early church in Rome (Catholic Church) is responsible for proclaiming December 25 as the birthday of Jesus Christ. There was no evidence that early church in the bible celebrated Christmas.
In fact, with many indications from the bible, it’s unlikely that the birth of Jesus was on the December 25. Palestine is very cold in December. It is too cold to ask everyone to return to their father’s land to register for taxes at this time. Shepherds do not stay in the field in winter.
Many people that celebrate Christmas now celebrate the birth of Jesus not necessarily because it’s the birthday of Jesus Christ.