Icelandic Christmas folklore features 13 Yule Lads who visit children before Christmas.
The Yule Lads, or Jólasveinar, are mischievous figures from Icelandic tradition. One arrives each night from 12 December through Christmas Eve, making 13 visitors in total. Children traditionally leave a shoe in a window, and a well-behaved child may find a small gift in it.
Each Yule Lad has a distinctive name and prank, such as Spoon-Licker, Door-Slammer, or Sausage-Swiper. Modern portrayals are generally friendlier than older stories, which sometimes described the figures as frightening.
The Yule Lads are associated with Grýla, a giantess said to be their mother, and the Christmas Cat. The 13-night schedule is sometimes confused with the 12 days of Christmas, but Iceland’s count specifically comes from the individual Yule Lads.