Why is Christmas celebrated on December 25?

The exact circumstances of the beginning of Christmas as we know it remain obscure. Some chronographers of the third century reckoned December 25, around the winter solstice, was the most likely day of Christ’s birth, although other dates had been suggested, including several dates in spring or fall. The oldest existing record of a feast to celebrate the birth of Christ in the western Church is in the Roman almanac called the Chronograph (or Chronography) of 354 or the Philocalian Calendar. This almanac noted that a festival commemorating Christ’s birth was observed by the Church in Rome in the year 336.

About 350 A.D., Pope Julius I set December 25 as the date when the Church would commemorate when Jesus was born. Many historians believe that the Church stirred up interest in a festival at this time of year to counter the pagan festivals surrounding the solstice, but no historical document unequivocally explains Rome’s reasons for setting the date as December 25.

The word “Christmas” comes from the Old English Cristes maesse, meaning “Christ’s Mass.”