Astronomical events since ancient times have been central to mankind. In the past they controlled the mating of animals, sowing of crops and metering of winter reserves between harvests. As a consequence, various cultural mythologies and traditions have arisen.
Today, December 21, is the winter solstice commonly known as the shortest day, but also as the beginning of longer daylight, therefore most cultures have held a recognition of rebirth, involving holidays, festivals, gatherings, rituals or other celebrations around that time.
Before the introduction of current calender, in the Julian calendar since 45 BCE the winter solstice of Europe was the 25th of December. But already in ancient Babylon, the feast of the Son of Isis (Goddess of Nature) was celebrated on December 25. Raucous partying, gluttonous eating and drinking, and gift-giving were traditions of this feast.
The Romans called their winter holiday Saturnalia, honouring Saturn, the God of Agriculture. In January, they observed the Kalends of January, which represented the triumph of life over death (does it ring a bell?). This whole season was called Dies Natalis Invicti Solis, the Birthday of the Unconquered Sun.
Mithraism was one of the major religions of the pre-Christian Roman Empire. It was the Cult of Mithra, the ancient Persian god of light and wisdom. In the Avesta (the sacred Zoroastrian writings of the ancient Persians) Mithra appears as the chief yazata (Avestan, “beneficent one”), or good spirit, and ruler of the world. Mithraism is similar to Christianity in many other respects, for example, in the ideals of humility and brotherly love, baptism, the rite of communion, the use of holy water, the priest were called father, the adoration of the shepherds at Mithra’s birth, the adoption of Sundays and of December 25 (Mithra’s birthday) as holy days, and the belief in the immortality of the soul, the last judgement, and the resurrection. Mithraism differed only in the exclusion of women from its ceremonies and in its willingness to compromise with polytheism.
These similarities made the conversion of its’ followers to Christianity easy. In 350, Pope Julius I also declared that Christ’s birth would be celebrated on December 25. There is little doubt that he was trying to make it as painless as possible for pagan Romans (who remained a majority at that time) to convert to Christianity.
In 1582 Pope Gregory XIII changed the calendar bringing the northern winter solstice to around December 21, for compensating the difference between the calendar year (365.2500 days) and the tropical year (365.2422 days). But major celebrations remained on December 25, offering us a magnificent example of how a ritual can overwhelm in importance its reason of being, also losing any contact with its origin.
Anyway, whichever is the god you worship, whoever the prophet you celebrate, I wish you a sunny year!