History and traditions of dating
Many Orthodox and Coptic Churches still use the Julian Calendar and so celebrate Christmas on the 7th January (which is when December 25th would have been on the Julian calendar).And the Armenian Apostolic Church celebrates it on the 6th January!The early Christians certainly had many arguments as to when it should be celebrated!
The Jewish festival of Lights, Hanukkah starts on the 25th of Kislev (the month in the Jewish calendar that occurs at about the same time as December).Christmas had also been celebrated by the early Church on January 6th, when they also celebrated the Epiphany (which means the revelation that Jesus was God's son) and the Baptism of Jesus.Now Epiphany mainly celebrates the visit of the Wise Men to the baby Jesus, but back then it celebrated both things!Some people also think that December 25th might have also been chosen because the Winter Solstice and the ancient pagan Roman midwinter festivals called 'Saturnalia' and 'Dies Natalis Solis Invicti' took place in December around this date - so it was a time when people already celebrated things.The Winter Solstice is the day where there is the shortest time between the sun rising and the sun setting. To pagans this meant that the winter was over and spring was coming and they had a festival to celebrate it and worshipped the sun for winning over the darkness of winter.
It's a time when family and friends come together and remember the good things they have.