
Celebrated at the 21st or 22nd of December Yule marks the Winter Solstice in the Northern Hemipshere while Litha is celebrated as the Summer Solstice in the Southern Hemisphere. It is of course close to Christmas Day while that is also the feast day of Frau Holle, a Scandinavian spirit who is honoured as the embodiment of nature and the woods. There's an article at that site on the History Of Yule and the various global celebrations held on or near the solstice. In the Southern Hemisphere it is the time of the Summer Solstice, Litha.
"The winter solstice in the Northern Hemisphere will fall on Sunday December 22 this year. It marks the first time in four years it hasn’t fallen on December 21, its most common date. The Winter Solstice will occur around 4.19am in the UK and there’ll be just seven hours, 49 minutes and 43 seconds of daylight in London – around nine hours less than in the summer solstice."
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Read more about Holly Kings, Yule Goats, and more winter customs