Your going to have to back that date up about 100 years there Johnnie according to this: Christmas celebration it was actually the Egyptian Theologians not the popes that started the celebrations. And that was around 200 AD. Not only that but a little paragraph in Wikipedia also show an alternative view on to why December 25 was chosen.
Quote
* The date of Christmas is based on the date of Good Friday, the day Jesus died. Since the exact date of Jesus' death is not stated in the Gospels, early Christians sought to calculate it, and arrived at either March 25 or April 6. To then calculate the date of Jesus' birth, they followed the ancient idea that Old Testament prophets died at an "integral age"—either an anniversary of their birth or of their conception. They reasoned that Jesus died on an anniversary of the Incarnation (his conception), so the date of his birth would have been nine months after the date of Good Friday—either December 25 or January 6. Thus, rather than the date of Christmas being appropriated from pagans by Christians, the opposite is held to have occurred. [See Duchesne (1902) and Talley (1986).]

Wikipedia: Origins of Christmas

So I don't believe we can blame it all on the popes.

Peter

If you believe what you like in the gospels, and reject what you don't like, it is not the gospel you believe, but yourself. Augustine of Hippo