The "original" Christmas date is unknown. The 6th January was, and still is, the feast of the Epiphany when the wise men came to visit Christ. The Church in Rome instituted Christmas to counter those who claimed that Christ was not really God made Man but only became Divine when he was older.

There is NO evidence that December 25th was any sort of pagan festival before Christians chose it for Christmas. You can find images of ancient Roman calendars from around the time of Christ. These show no festival on Dec 25th. There is NO record of any birth day for Mithras. Even the supposed "Natalis Invicti" feast day is dubious and, if it existed at all, came after Christmas started, Romans did not celebrate the Solstice – their festival around that time (Dec 17th), Saturnalia, was a harvest festival.

The Feast of the Resurrection, Easter in English, was celebrated by the church from its earliest days. There are records of Easter services from the 2nd century. There was a debate in the church about which day to celebrate which settled on the Sunday after Passover – Sunday being already know as "The Lord’s Day". Because of its link to Passover, the feast was named the Christian Passover – Pascha in Latin (in modern times Pascua in Spanish, Paques in French and so on).

Over 400 years later, Christianity reached the Anglo-Saxons, they were taught about the Paschal Season which happened to coincide with their month of Eosturmonath. The ordinary people therefore translated Pascha as Eostur, later Easter, though the church, which used Latin, continued to call it Pascha until the reformation.

The early English writer Bede speculated that Eosturmonath had, many years earlier, been named after a goddess Eostre whose worship had died out. Unfortunately, absolutely nothing else is known about this supposed Goddess. She appears in NO anglo-saxon myths or legends, she has NO known feast day, she has NO known temple or site, NO known dedication.. Modern scholars have concluded that she was probably made up by Bede to explain the month name and was never actually a goddess at all.
References :
"Stations of the Sun", Professor Ronald Hutton, Oxford University Press 1996

Many of these holidays were modified by the early Church to ease the conversion of local Pagans from their practices to those of the Christian Church. If the Church used the same dates, and slowly altered the underlying message or purpose of the festival, they could rid the area of pagan practices all together. And it nearly worked. Those Pagans that didn’t convert went underground so to speak with their practices and kept their beliefs alive. While no pagan tradition today can directly link their practices of today with an ancient tradition, the elements and oral traditions have been kept alive. Even if some of those are from anthropological study and research.

But holidays aren’t the only Pagan influences you’ll find in a Christian Church. There are many pagan rituals that are incorporated into Christian worship.

~ Catholicism utilizes the use of incense to bless the altar before Mass. A Pagan form of clearing energy and setting shields of protection around an altar before ritual.
~ Most Christian churches light candles upon their altar to beckon the presence of Yahweh and Jesus. A Pagan form of honoring and calling the Gods/Goddesses to ritual.
~ Prayer is a petition to Yahweh for aid or to honor. Closely related to casting a Spell and invoking a God/Goddess for aid or to honor.
~ Using symbology upon an altar such as a cross or image of Jesus is also a Pagan practice used to focus energy or align one’s energy with a particular Deity or spirit (ie: an animal spirit).
~ One of the biggest uses of symbology in the Christian church is drinking wine for the blood of Jesus and eating bread for the bones of Jesus. This is an extremely pagan thing to do. By taking in the essence of the "god" into your body you are not just aligning your energies with that Deity, but you are also channeling that "god" through your body.

Whither or not some Christians want to admit it or not, we are all much more alike than we are different. Wouldn’t it be great if we could focus on our similarities instead of our differences and learn tolerance for each other?
References :
The History Of Samhain / Halloween http://paganspath.com/magik/samhain-history.htm
The History of Yule and the Winter Solstice @ http://paganspath.com/magik/yule-history.htm

~ Celtic Shaman, Teacher & Pagan

Only when theses and like things are stoped will christiality be christianity!
References :