Christmas, also known as Christmas Day or Christmastide, is an annual holiday falling on December 25 or January 7 that honors and celebrates the birth of Jesus of Nazareth. His birth, which is the basis for the transcultural Western calendar, has been determined by modern historians as having occurred between 8–4 BC, and is traditionally told to have taken place in a stable within the city of Bethlehem. The specific date of celebration for Jesus' birth is traditional, and is generally believed to have been influenced by the dates of pre-Christian festivals—usually the Roman festival of Dies Natalis Solis Invicti — rather than having been based on historical data or reference.