The season that people celebrate as Christmas, falling on the 25th of December was a pagan celebration which commemorated the rebirth of the pagan sun god.

During the season of winter solstice which falls on the 21st of december, the sun light becomes covered with darkness, resulting into the darkness or night becoming longer than the day in winter time Northern Hemisphere, (being also the most darkest and coldest season of the winter).

For those countries that are located on the north hemisphere winter nights or darkness becomes longer than the day.

The winter solstice is the time when the Germanic festival of Yule and the eating of Yule boar (Christmas Ham) was celebrated. Christmas was transplanted into winter solstice about 1,600 years ago, centuries before the English language emerged from its Germanic roots.

The 25th of December celebrated as a pagan festival way before the existence of Christmas:
Winter Solstice had been associated with the birth of a “Divine sun god” long before the rise of Christianity. Since the Sun is considered to represent the Male Divinity in many Pagan Traditions, this time is celebrated as the “return of the Sun god” where He is reborn of the Goddess.

However, it is believed that this date was chosen to offset pagan celebrations of Saturnalia and Natalis Invicti. Some believe that celebrating the birth of the “true light of the world” being the sun god and Saturnalia was set in synchronization with Christianity, and from it came what is known today as Christmas.

December solstice because from that point (25th of december) and onwards, the days began to have more daylight in the northern hemisphere.

25th also being the birthday of Nimrod (the king who was in charge of building the tower of babel) who claimed to be a god, this day became a pagan ritual which commemorates the rebirth of the sun god and the celebration of Nimrod as a god.

In Ancient Rome Christmas comemorated the celebration of Bacchus, in Ancient Greece this festival was linked to Dionysus.
In Scandinavia Christmas is also known as Yule tide
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