why do we celebrate christmas on december 25

Christmas is celebrated on December 25 because early Christians, starting in the 4th century, chose this date to commemorate the birth of Jesus Christ. The actual birth date of Jesus is unknown, but December 25 was likely selected due to its alignment with ancient Roman pagan festivals such as the winter solstice celebrations, Saturnalia, and the birthday of the sun god Mithras, which marked the return of longer daylight after the shortest day of the year. Another influential tradition linked December 25 to the date of Jesus’ conception on March 25, which was also believed to be the date of his crucifixion, making nine months until December 25 the symbolic date for his birth. The choice of this date was also politically motivated under Emperor Constantine to align Christian celebrations with existing pagan festivities and ease the empire’s transition to Christianity.