You better watch out, you better not cry or you might end up with a rotten potato in your shoe. Yep, a rotten potato.
It is December 12th and the Icelandic Yule Lads are coming or at least the first Yule Lad. On December 12, Stekkjarstaur (in English that is a Sheep-Cote Clod) appears. He harasses sheep, but is impaired by his stiff peg-legs.
What, or who, are the Yule Lads? They are figures from Icelandic folklore, portrayed as being mischievous pranksters, but who have in modern times also been depicted as taking on a more benevolent role similar to Santa Claus. While their number has changed over time, currently there are considered to be 
thirteen. They put rewards, or punishments, into shoes placed by children on window sills during the last thirteen nights before Christmas. Every night, one Yuletide lad visits each child, leaving gifts or rotting potatoes, depending on the child’s behavior throughout the year.
In 1932, the poem “Jólasveinarnir” was published as a part of the popular poetry book Jólin Koma (“Christmas Is Coming”) by Icelandic poet Jóhannes úr Kötlum. The poem reintroduced Icelandic society to Icelandic Yuletide folklore and established what is now considered the canonical thirteen Yule Lads, their personalities and connection to other folkloric characters. You can read the poem here: The Yule Lads Poem.
The Yule Lads were once portrayed as being mischievous, or even criminal, pranksters who sometimes steal from, or otherwise harass the population, and all have descriptive names that convey their modus operandi.
In recent times the Yule Lads have been depicted as taking on a more benevolent role comparable to Santa Claus. This was probably done to prevent nightmares of the original concept of child eating creatures.
The really scary ones are the Yule Lads parents who are just made to be featured as “unsubs” (unknown subjects) on the TV show “Criminal Minds.” Mom and dad are said to be mountain-dwelling trolls Grýla and her husband, Leppalúði. Grýla is big and scary, with an appetite for the flesh of mischievous children, whom she is sometimes depicted as putting in a large pot and make into stew. Grýla is said to come down from the mountains to scare Icelandic children who misbehaved before Christmas. Her husband is smaller and weaker, and mostly stays at home in his cave, lazy and mindless. They are depicted with the Yule Cat, a beast that, according to folklore, eats children who do not receive new clothes for Christmas. I suspect this is a ploy to make kids happy to get clothes as a gift.
As the National Museum of Iceland describes today, the Yule Lads are:
- Sheep-Cote Clod (Stekkjarstaur): He tries to suckle yews in farmer’s sheep sheds
- Gully Gawk (Giljagaur): He steals foam from buckets of cow milk
- Stubby(Stúfur): He’s short and steals food from frying pans
- Spoon Licker (Þvörusleikir): He licks spoons
- Pot Scraper, aka Pot Licker (Pottaskefill): He steals unwashed pots and licks them clean
- Bowl Licker (Askasleikir): He steals bowls of food from under the bed (back in the old days, Icelanders used to sometimes store bowls of food there – convenient for midnight snacking?)
- Door Slammer (Hurðaskellir): He stomps around and slams doors, keeping everyone awake
- Skyr Gobbler (Skyrgámur): He eats up all the Icelandic yogurt (skyr)
- Sausage Swiper (Bjúgnakrækir): He loves stolen sausages
- Window Peeper (Gluggagægir): He likes to creep outside windows and sometimes steal the stuff he sees inside
- Door Sniffer (Gáttaþefur): He has a huge nose and an insatiable appetite for stolen baked goods
- Meat Hook (Ketkrókur): He snatches up any meat left out, especially smoked lamb
- Candle Beggar (Kertasníkir): He steals candles, which used to be sought-after items in Iceland
You can get a chart with a list of the Yule Lads here: Yule Lads List
If you want to have a little fun, you can take a quiz to find out which Icelandic Yule Lad are you most like here.
The Yule Lads are just part of all the wonderful folklore in Scandinavia. You can find a wonderful assortment of folklore books at Ingebretsen’s store and online.