Winter Solstice celebrations are held on the eve of the shortest day of the year. During the first millennium in what is today Scotland, the Druids celebrated Winter Solstice honoring their Sun God and rejoicing his return as the days got longer, signaling the coming of spring. Also called Yule, this tradition still lives today in the Wiccan traditions and in many cultures around the world.
A huge log (the Yule Log) is brought into an outdoor clearing and becomes part of a great bonfire. Everyone dances and sings around the fire. All the noise and great excitement is said to awaken the sun from its long winter sleep, hurrying spring on its way as the cycle begins once again and the days grow longer than the nights.
Mistletoe and the oak trees it grew in were sacred to the ancient druids and a symbol of eternal life the same way as the Christmas tree. It was also thought to have medicinal powers.
The Romans valued it as a symbol of peace and this lead eventually to its acceptance among Christmas props. Kissing under the mistletoe was a Roman custom, too.
Evergreens were cherished at this time of year as a natural symbol of rebirth and life amid winter whiteness. But holly was particularly prized to decorate doors, windows and fireplaces because of its prickliness -- (holly was supposed to be hateful to witches) to either ward off or snag and capture evil spirits before they could enter and harm a household.
Holly was admired by the heathen Druids, who believed that its evergreen leaves attested to the fact that the sun never deserted it, and since the sun was held in worship, holly was sacred.
Medieval Christmas folklore seems endless: that animals will all kneel down as the Holy Night arrives, that bees hum the '100th Psalm' on Christmas Eve, that a windy Christmas will bring good luck, that a person born on Christmas Day can see the Little People, that a cricket on the hearth brings good luck, that if one opens all the doors of the house at midnight all the evil spirits will depart, that you will have one lucky month for each Christmas pudding you sample, that the tree must be taken down by Twelfth Night or bad luck is sure to follow, that 'if Christmas on a Sunday be, a windy winter we shall see,' that 'hours of sun on Christmas Day, so many frosts in the month of May,' that one can use the Twelve Days of Christmas to predict the weather for each of the twelve months of the coming year, and so on.