*In Europe, the winter solstice was celebrated with bonfires and rituals.
The Roman Saturnalia lasted several days in December. The people gambled.
The Germanic tribes also celebrated mid-winter by drinking alcohol. The Bulgarian and the Polish (with Koleduvane and Gwiazdka) perpetuated this tradition.
Jesus of Nazareth was probably born in springtime (but Reformists think that Jesus was born in autumn).
But in the 4th century, Pope Julius I chose December 25th for the celebration of the birth of Jesus. Thus, a Christian element was introduced in the long-established mid-winter festivals.