Along with Santa Claus and Krampus, Gryla is an actual myth associated with winter, possibly the oldest one. Of Icelandic origin, Gryla was an ogre with 13 sons, the Yule Lads. Gryla would tour the world on winter nights, asking for charity for her sons. Legend has it that, if she was denied charity, her sons would enter the dwelling and cause mischief until the owner begged Gryla to retrieve them. The idea of shape-shifting abilities and handing out punishment are later additions to the myth, borrowed from the Wild Hunt, another Nordic legend in which a pack of ghost hunters (Odin's entourage) would often give worthless gifts to kind strangers, like a bag of coal or a manure. If accepted this worthless gift would turn into gold the next day.
The word "Kavalame" that Nick uses on his reindeer translates to "we ride" in Greek.
Krampus the demon has been a part of the Yule legend for centuries. He traditionally accompanied St. Nicholas and dispensed lumps of coal or an occasional switching with a stick to the bad children. His night is celebrated on December 5th, the day before St. Nicholas makes his rounds on the 6th. It's a huge, often raucous celebration in many parts of the world, though now done in fun. Eventually, St. Nicholas morphed into Santa Claus in many traditions, but the feast of St. Nicholas, Bishop of Myra, is still an important holiday in Belgium and the Netherlands. Myra is a city in present day Turkey, where Nicholas lived in the 3rd and 4th centuries A.D.
Originally meant to be premiere on Prime Video, but was given a theatrical release instead.
Chris Evans dropped out of the film Fly Me to the Moon (2024) with Scarlett Johansson to star in this film. He was later replaced by Channing Tatum.