According to Icelandic Yule (jól in Icelandic) folklore there are 13 Yule Lads (jólasveinar). They are the sons of the trolls Grýla and Leppalúði, who are first mentioned in Snorra Edda, an 800 year old Icelandic historical script, although the Yule Lads only appear in folklore in the 17th century.

The Yule Lads are said to have terrorised people for 13 days before Yule, one lad each day, either stealing or pulling pranks, and were often used to scare children into behaving well. Their mom, Grýla, is said to have collected naughty children in a sack, bringing them to her cave and eating them (similar to Krampus). There is also the Yule Cat (jólakötturinn), who was about five meters tall (over 16 feet), and he came after children that didn't get new clothes before Yule.

Today, the Yule Lads have become kind and fun (although still pulling pranks). For 13 nights before Yule, they give children that leave their shoes in their window, treats, small toys or mandarins. Naughty children only get raw potatoes.

Grýla is said to have had about 80 children but only the 13 Yule Lads are commonly known. Their names are:

Stekkjastaur - Sheep-Cote Clad

Giljagaur - Gully Gawk

Stúfur - Stubby

Þvörusleikir - Spoon Licker

Pottasleikir - Pot Licker

Askasleikir - Bowl Licker

Hurðaskellir - Door Slammer

Skyrgámur - Skyr Gobbler

Bjúgnakrækir - Sausage Swiper

Gluggagægir - Window Peeper

Gáttaþefur - Door Sniffer

Ketkrókur - Meat Hook

Kertasnýkir - Candle Beggar

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