Just a little bit of Christian history some might not know about:
The book, The Sun in the Church reveals that many medieval Catholic churches were also built as solar observatories. The church, once again reinforcing the close ties between religious celebration and seasonal passages, needed astronomy to predict the date of Easter. And so observatories were built into cathedrals and churches throughout Europe. Typically, a small hole in the roof admitted a beam of sunlight, which would trace a path along the floor. The path, called the meridian line, was often marked by inlays and zodiacal motifs. The position at noon throughout the year, including the extremes of the solstices, was also carefully marked.
also
Holy Blood, Holy Grail discusses the pragmatic political motives of the fourth-century Roman emperor Constantine, who first moved the celebration of Christmas to December 25. The authors claim that Constantine followed the cult of Sol Invictus, a monotheistic form of sun worship that originated in Syria and was imposed by Roman emperors on their subjects a century earlier.
In the interests of unity, Constantine deliberately chose to blur the distinctions among Christianity, Mithraism [another Sun cult of the time] and Sol Invictus. This is the reason why Constantine decreed that Sunday — “the venerable day of the sun” would be the official day of rest. Early Christians before that time celebrated their holy day on the Jewish Sabbath, Saturday. That’s also why, by his edict, the book further claims, the celebration of Jesus’ birthday was moved from January 6th (Epiphany today) to December 25, celebrated by the cult of Sol Invictus as Natilis Invictus, the rebirth of the sun. The cult of Sol Invictus (Unconquered Sun) was a comparatively late (3rd century BCE) arrival from the East (Syria). It became the chief imperial cult of the Roman Empire, until it was replaced by Christianity. In the old calendar the winter solstice (Bruma = shortest [day]) fell on Dec. 25, so this was the day on which Sol proved Himself to be yet unconquered.
The 12 Days of Christmas — The midwinter festival of the ancient Egyptians celebrated the birth of Horus – son of Isis (the divine mother-goddess). The celebration was 12 days long, reflecting their 12-month calendar. 12 Around 1 The Alchemy of Time
This concept took firm root in many other cultures. In 567 AD, Christians adopted it. Church leaders proclaimed the 12 days from December 25 to Epiphany as a sacred, festive season.
This winter holiday/holyday season is rooted in almost every culture. It’s too bad that some religions insist on taking credit for it all.