When exactly is Christmas Day?
No one knows when Jesus was born. Early Christians tried to calculate the date of Christ’s birth based on the Annunciation, 25 March, the Bible’s first account of when Mary was told she was pregnant. If this is taken as the conception of Christ, nine months later it is 25 December.
But Jewish tradition has it that Jesus was born during Hanuk-kah, 25 Kislev into the beginning of Tevet. In the Julian calendar, 25 Kislev would be 25 November.
Others say Jesus and Mohammed shared the same birthday. Mohammed was born on the 12th of the Muslim month of Rabi-ul-awal in the 7th century which this year was celebrated in April. Muslims use a lunar calendar, so Mohammed’s birthday will eventually fall in December. Most Eastern Orthodox churches celebrate Christmas on 7 January.
Christmas was first celebrated on 25 December in the 5th century in the time of the Constantine, the first Christian Roman emperor. This date was probably chosen because the winter solstice and the ancient pagan Roman midwinter festival called Saturnalia was in December. The winter solstice is the day with the shortest time between the sun rising and setting. It falls between 22 and 25 December.