Long before Christmas, people celebrated the Winter Solstice. People felt the celebrations made the Sun God happy and hurried the coming of Spring. Celebrations were held on the eve of the shortest day of the year.
A big log, called the Yule Log was burned in a great bonfire. Everyone danced and sang around the fire. Families hung mistletoe from the doorways of their homes for good luck. Some people decorated their homes with evergreens.
As you can see, many of the Winter Solstice traditions were made a part of the Christmas traditions as more people became Christians. The Winter Solstice is still celebrated, however, by many cultures around the world and is also a part of the Wiccan religion.