Midwinter, or Winter Solstice, which is marked around 21 December, has been recognized as a significant turning point in the yearly cycle since the late Stone Age. The ancient megalithic sites of Newgrange and Stonehenge, carefully aligned with the winter solstice sunrise and sunset, exemplify this. This position in the Wheel of the Year is sometimes referred to by the term "Yule", after the Germanic and later Northern European winter festival of the same name.
Obviously there is a lot of overlap between each of the winter traditions (Yule, Winter Solstice, Christmas and Saturnalia) so many of the things in this collection appear also in the Christmas / Saturnalia collection. It will be worth your while to check out both, however, as we have tried to place the more obviously solstice things in this collection and the more traditionally Christmassy ones in that collection.
