It is because the Earth is tilted on its axis as it revolves around the sun that our year has its four seasons. Today the North Pole is turned as far away from the sun as it will go, while the South Pole is turned towards the sun, and it is the Summer Solstice. The cause of the seasons is the angle of the sunlight as it reaches the Earth. The more a hemisphere is turned away from the sun, the less sunlight and heat it receives, bringing on winter. The more it faces the sun, the more heat and light it receives, resulting in summer.
At the equator, where the angle of the sun is always the same, the sun at noon seems to be directly overhead, and the length of the days and nights is equal. In other parts of the world, the sun is highest in the sky on the day of the Summer Solstice. Every day that follows, the sun appears to follow a lower course through the sky and shorter distance from east to west, until at the Winter Solstice in the northern hemisphere it reaches its low point in the south.
Northern Winter Solstice at right Earth at Northern Winter Solstice
The word "solstice" comes from the Latin roots meaning "sun" and "stand." The Winter Solstice is the day when the sun appears to stop its progression lower in the sky and stand still, before reversing course. It marks the lowest point of the sun and the shortest day, but it also means that the sun will begin to rise in the sky, and the days will begin to grow longer.
Worldwide, the solstices are often marked by traditional festivals, and it is likely that they have been for thousands of years. Our ancient ancestors were very much aware of the progression of the seasons. There is strong evidence that marking the solstices was of great importance to many neolithic cultures. The monument of Stonehenge, built five thousand years ago, is roughly aligned with sunrise on the Summer Solstice.
Once agriculture began, it became increasingly important to be able to calculate the change in seasons, to know when to plant the annual crops. Some ancient cultures, notably in Mesopotamia, developed impressive skill in astronomy and mathematics. Among the first things they probably would have calculated, as easiest to predict, would be the dates of the solstices and equinoxes.
In many ancient cultures, the seasonal progression was also closely tied to myth, and to the celebration of annual festivals marking the turn of seasons. The advent of spring, for example, was commonly tied to the annual rebirth of a vegetation god.
It is often supposed today that the Winter Solstice worldwide used to be the date of solar festivals, celebrating the birth or rebirth of a sun god; accounts of such Winter Solstice celebrations can be found on many popular websites. Unfortunately, these accounts often owe more to the imagination of popular anthropologists than fact. Examination of the sources suggests that Winter Solstice celebrations were not always tied directly to the birth of a solar deity. It seems that many people today think that ancient peoples should have had such beliefs, and so they found them where they may not have actually existed, or where there is no real evidence for them.
There are reasons why the ancient cultures of the Mediterranean may not have considered the Winter Solstice such an important date. This region is close enough to the equator that the difference in the length of days and nights is less noticeable than it is farther north. The coming of winter was not of such importance as the coming of spring, which was more often celebrated as the time of renewal and the new year.
When solstice festivals were held, they were not always directly related to a sun god. One of the most important holidays in Rome was the Saturnalia, celebrated around the time of the Winter Solstice, sometimes lasting an entire week. It was a festival of reversal and misrule, when work was forbidden and slaves and masters might exchange roles. But Saturn was not a sun god, and there is no evidence that the time of his festival was directly related to the position of the sun.
Much later in the Roman Empire, about the time that Christmas began to be observed, the Emperor Aurelian created the festival of Sol Invictus, the unconquered sun. This, without a doubt, was a solstice festival, but little is known about it, except as an aspect of the imperial cult; the emperor was often depicted as the sun at this period. It may have been related to Mithraism, which was an important and popular religion in the late empire, but there is no clear evidence that Mithra was a sun god, or that he was born on the solstice, despite numerous claims. In the Persian tradition, the feast of Mithra was held in the autumn.
In regions farther north, where the shortening of the days and the harshness of winter were more noticeable, it is natural that Winter Solstice festivals would have assumed greater importance. Among the Germanic peoples, the time of the solstice was known as Yule. While it is often supposed that the traditions of the Christmas festival in medieval Europe were derived from Yule, there is not a lot of direct evidence for this. In fact, we have very little direct information about the religious traditions of the ancient Germanic peoples.
Yule among the Anglo-Saxons referred to the months of December and January, the entire Winter Solstice season. Sacrifices were made during this season, and there was feasting. At Uppsala in Sweden, the center of the worship of the god Freyr, there were both animal and human sacrifices. The boar was sacred to Freyr, and the tradition of serving a boar's head at the Yule feast, as commemorated in the "Boar's Head Carol," may recall this sacrifice. Freyr, however, was a fertility god, not a sun god.
Lighting a Yule Log may be another surviving remnant of ancient Germanic practice, as well as the use of the mistletoe at this season. In some Scandinavian regions, Yule Goats made out of straw are displayed, which may relate to the god Thor.
On or near the day of the solstice itself, the Anglo-Saxons had a festival known as Modranicht, or Mothers Night. The identity of the Mothers is not known, but it is possible that they were goddesses of the underworld, or the dead. The association of the god Wotan, or Odin, with the Yule season suggests that it may have been a feast of the dead, rather than a solar festival. In that case, Yule would have been much like the Celtic Samhain, which survives as our Halloween - a dark and scary time, rather than a celebration of the return of light. The tradition of wassailing greatly resembles the custom now known as Trick-or-Treat.
Traditions in some other cultures correspond more closely to the idea of a solstice solar myth. In Japan, the sun goddess Amaterasu is the most important deity and the ancestor of the imperial family. According to the myth, the sun goddess was so distressed by the misrule of her brother on Earth that she withdrew into a cave, bringing darkness on the world. The other gods had to trick her into coming out, and the Winter Solstice, Toji, is the date of her emerging from the cave and returning the light to the world. This festival has been more recently overshadowed by others, in particular the January celebration of the New Year.
In Peru, the sun festival of Inti Raymi is held on June 24, celebrating the Winter Solstice in the southern hemisphere. Inti was the Inca god of the sun, the primary Inca god. For three days before the festival, all fires were extinguished, and a new fire was kindled by focusing the rays of the sun. Toasts of chicha were made to the god, and llamas were sacrificed. This festival is reenacted every year in Cuzco, Peru, as a celebration of Inca heritage, although the sacrifice of llamas is now only symbolic.
Tonight, on the Winter Solstice, I look outside my window and see the neighborhood houses blazing with lights, and illuminated Christmas trees in the windows. These are the traditions of today, lights in the season of darkness.
Christmas trees, and most medieval Christmas traditions, were once condemned by the Puritans as pagan. However, it is highly unlikely that the ancient Germanic tribes illuminated fir trees with candles, as in the tradition introduced into England from Germany by Prince Albert in 1850.
Sometimes traditions become popular simply because people enjoy them and find them fitting to a seasonal celebration.
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