According to History.com the original roots of this tradition go back all the way to ancient Norse mythology. Odin, the most important Norse god, was said to have an eight-legged horse named Sleipner, which he rode with a raven perched on each shoulder. During the Yule season, children would leave food out for Sleipner, in the hopes that Odin would stop by on his travels and leave gifts in return. Such a tradition continues today in countries such as Denmark, Belgium and the Netherlands, where children still believe that horses carry Santa’s sleigh instead of reindeer. On Christmas Eve, they leave carrots and hay—sometimes stuffed into shoes—to feed the exhausted animals. In return, they might hope to receive such holiday treats as chocolate coins, cocoa, mandarin oranges and marzipan.
Over the years, different countries have developed their own versions of the tradition. Here our children leave out sherry and mince pies, while Swedish kids leave rice porridge. Santa can expect a pint of Guinness along with his cookies when delivering toys in Ireland. French children leave out a glass of wine for Père Noël and fill their shoes with hay, carrots and other treats for his donkey, Gui (French for “mistletoe”). In Germany, children skip the snacks altogether and leave handwritten letters for the Christkind, a symbolic representation of the Christmas spirit who is responsible for bringing presents on Christmas. Though many German kids mail their letters before the holiday—there are six official addresses for letters addressed to the Christkind—others leave them out on Christmas Eve, decorated with sparkly glue or sugar crystals. On Christmas morning, the letters have been collected, and gifts left in their place.