These religious references reveal the clash and melding of folk beliefs and new religion as Christianity crept into Europe. In different tales at different times, elves alternated between good and bad, Hall wrote.
They could deliver babies safely through a difficult labor -- or steal away a human baby and replace it with a sickly and deformed changeling. Elves, known as alp in German, could cause nightmares (Alpdrück), perhaps similar to other mythology surrounding the scary experience of sleep paralysis. Nevertheless, elves were probably still considered human-size, rather than diminutive, Hall wrote.
By William Shakespeare's day, elves lost many of their malevolent undertones. Shakespeare's "A Midsummer Night's Dream," written in the 1590s, included an elflike figure, Puck, who acted as a jokester or trickster.
From myth to Christmas
Much as the modern Thanksgiving menu dates back to the 1800s, so too do modern U.S. Christmas traditions. Elves became linked with Santa Claus in the 1823 poem "A Visit from St. Nicholas," better known today as "The Night Before Christmas." That poem refers to Santa Claus as a "jolly old elf."
With the elf-Christmas link established, other writers began to get creative with the idea. In 1857, Harper's Weekly published a poem called "The Wonders of Santa Claus," which tells how Santa "keeps a great many elves at work/ All working with all their might/ To make a million of pretty things/ Cakes, sugar-plums, and toys/ To fill the stockings, hung up you know/ By the little girls and boys."
The idea caught on. In 1922, famed artist Norman Rockwell released a painting of an exhausted Santa surrounded by tiny, industrious elves, trying to get a dollhouse finished in time for Christmas. A 1932 short movie by Disney called "Santa's Workshop" showed bearded, blue-clad elves singing, prepping Santa's sleigh, brushing reindeer teeth and helping Santa with the naughty/nice list. "Molly seems to be OK; she eats her spinach every day," an elf rhymes, before nixing another child's ambitious list because he doesn't wash behind his ears. [6 Surprising Facts About Reindeer]
The modern era has brought nonconformist elves to the forefront, first in the form of Hermey the Misfit Elf in 1964's now-classic TV special, "Rudolph the Red-Nosed Reindeer." (Hermey preferred dentistry to servitude in Santa's workshop.) And in 2003, the comedy "Elf" starred Will Ferrell as a human brought up by Santa's elves who must travel to New York City to find his biological family.
The latest in elf innovation, the Elf on the Shelf, gives elves a duty they've never had before: not just making toys, but also serving as Santa's informants. In some ways, however, the Elf on the Shelf's arguable creepiness gets back to Christmas' roots. In Iceland, Gunnell said, children don't await Santa Claus; they wait for 13 "Yule Lads," who leave gifts in their shoes. Nor do they traditionally fear a lump of coal as a consequence of bad behavior. In Icelandic lore, the horrifying ogress Grýla eats up naughty children.
Likewise, Icelanders' beliefs about elves are closer to the concepts seen in ancient tales. As of 2007, about 37 percent of Icelanders said it was "possible" that álfar still roamed the countryside, another 17 percent said it was "probable" and 8 percent were certain elves were still afoot, Gunnell said. He compared the reluctance to discount elves with other common folk beliefs around the world, such as the notion that the dead might be able to contact the living.
"It's quite nice for your children to have a sense of the landscape like this, to have a sense of magic," Gunnell said. Americans, he argued, are looking for the same magic with both their Christmas traditions and their leisure activities.
"What you have in America is a longing for elves," he said. "This is the popularity of "Game of Thrones," "Lord of the Rings" -- you name it."
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