According to Wikipedia:
"The winter solstice occurs at the instant when the Sun's position in the sky is at its greatest angular distance on the other side of the equatorial plane as the observer. Depending on the shift of the calendar, the event of the Winter solstice occurs sometime between December 20 and 23 each year in the Northern hemisphere, and between June 20 and 23 in the Southern Hemisphere, and the winter solstice occurs during either the shortest day or the longest night of the year (not to be confused with the darkest day or nights). Though the Winter Solstice lasts an instant, the term is also used to refer to the full 24-hour period.
"Worldwide, interpretation of the event has varied from culture to culture, but most cultures have held a recognition of rebirth, involving holidays, festivals, gatherings, rituals or other celebrations around that time....
"On the night of Winter Solstice, as seen from a northern sky, the three stars in Orion's belt align with the brightest star in the Eastern sky Sirius to show where the Sun will rise in the morning after Winter Solstice. Until this time, the Sun has exhibited since Summer Solstice a decreasing arc across the Southern sky. On Winter Solstice, the Sun ceased to decline in the sky and the length of daylight reaches its minimum for three days. At such a time, the Sun begins its ascent and days grow longer. Thus the interpretation by many cultures of a sun reborn and a return to light. This return to light is again celebrated (at the vernal equinox, when the length of day equals that of night."
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A partial list of holidays/festivals (past and present) occurring around the Winter Solstice:
Zagmuk, Sacaea. Saturnalia, Yuletide, Sankranti, Brumalia, Dies Natalis Solis Invicti, Hanukkah, Alban Arthuan/Midwinter, Finn's Day, Festival of Sol, Festival of the New Sun, Festival of Growth, Great Day of the Cauldron, Dong Zhi, Nollaig, Juul, Jul, Jiueis, Jol, Joulu, Joulupukki, Children's Day, Festival of Kronos, Kallikantzaroi, Karkantzaroi, Dazh Boh, Chaomos, Inti Raymi, Soyal, Sada, Touji, Geol, Feailly Geul, Modra-niht, Giuli, Iol, J--lmnu_r, Shass Greiney Geuree, Yn Ad-Gheurey, Divalia, Larentalia, Sigillaria, Midvinterblot, Touji, if Inti Raymi, Shabe-Yalda, Sviatki, Koleda, Choimus, Soyalangwul, Diwali, Sadeh, Adur-Jashan, Maidyarem, Shab e Cheleh, Novo Hel, Nollaig, Pongal, Modranetc, Yalda, Karachun, St. Thomas' Day, Christmas (Xmas), The Festival of the Long Night, Wintervil, Zamenhof Day, Festivus, Human Light, Chrismukkah, Giftmas, Newtonmas, Kwanzaa, Boxing Day, Lenaea (Festival of the Wild Women).
Some of the god-men that were supposedly born around this time:
Adonia, Attis, Baal, Dionysus, Helios, Hercules, Mithra, Osiris, Perseus, Theseus, Jesus, and King Arthur.
See also:
Dates and Times of Equinoxes and Solstices
