Yule is a winter festival celebrated in Northern Europe since ancient times. In pre-Christian times, Germanic pagans celebrated Yule in late December or early January on a date determined by a lunar calendar. During the process of Christianization and the adoption of the Julian calendar, Yule was placed on December 25, in order to correspond with the Christian celebrations later known in English as Christmas. Thus, the terms "Yule" and "Christmas" are often used interchangeably, especially in Christmas carols.
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