A lot of stories in Norse mythology deal with how different parts of the mythological world – beings, magical objects, landscapes, buildings – came to be. "The Walling of Asgard" is one of these stories. It gives an account of how Asgard gained its enormous protective wall and how Odin got his magical eight-legged steed, Sleipnir.
Like many of the legends we know about the gods of Asgard, this one is recorded in Snorri Sturluson's 13th-century Prose Edda in the Gylfaginning, or Tricking of Gylfi. King Gylfi attempts to travel to the land of the gods, but instead ends up in a mysterious in-between land where he must engage in a wisdom-contest, asking questions about the Norse cosmos and mythology. The story describing the walling of Asgard is the tale a character named High tells in response to Gylfi's question, "Who owns that horse Sleipnir, and what is to be said of him?" (Prose Edda, Gylfaginning, Chapter 42, p. 55).
It turns out there's quite a lot to be said about Sleipnir. For one thing, he's the love child of the amazingly strong stallion Svadilfari and the trickster-god Loki. Loki is absolutely infamous for producing mutant, monstrous children. With his giantess wife, Angrboda, Loki spawns 1) an enormous sea-serpent; 2) a fierce, world-swallowing wolf; and 3) the ruler of the Underworld. So, it's not surprising that Sleipnir's no ordinary horse. He's got eight legs, and these seem to make him faster than any other horse. Also, maybe because he's the half-brother of its ruler, he's the only horse who can carry his rider to the Underworld.
In a popular 13th-century Icelandic saga (sort of like the Viking version of a medieval romance) the trickster-hero Gestumblindi poses the following riddle:
Who are the twain
that on ten feet run?
three eyes they have
but only one tail.
(From "Heiðreks gátur," Hervarar saga ok Heiðreksin Old
The answer, of course, is the one-eyed god, Odin, riding on Sleipnir the eight-legged horse. The fact that Sleipnir was the subject of a riddle in a popular saga suggests that everybody was familiar with Odin's horse. The archaeological record supports this conclusion: two 8th-century memorial stones from Gotland, Sweden depict an eight-legged horse carrying a rider. In one, a Valkyrie greets the rider with a cup, suggesting that Sleipnir has carried him to the world of the dead. Popular legend in Iceland also attributes the horseshoe-shaped canyon Asbyrgi to the imprint of Sleipnir's hoof.
With Sleipnir such a well-known mythical figure, possessing so many mysterious powers (and so many limbs), is it any wonder that the story of his origin is an elaborate tale of intrigue, magic, and mayhem?
Let's set the scene. The gods have already created Middle-Earth and Valhalla, which is a good thing, because these put some space between Asgard (the land of the Aesir gods) and Jotunheim (the land of the giants). But the gods are a bit paranoid. They're worried that a particularly crafty giant (called a Jotun) will somehow make his way through two other worlds, across the rainbow bridge, and into Asgard.
That's why they're so eager to take the mysterious stone-mason up on his offer to build a gigantic wall around Asgard. With the protection the stone-mason proposes, the gods are convinced they'll never have to worry about a giant-invasion ever again. What they don't realize is that, by accepting the stone-mason's offer, they're inviting a giant into Asgard. Oops.
The stone-mason (who by now we realize is really a giant) promises to complete his work in a single winter. His work must be finished by the first day of summer, or else he won't be paid. Summer was the time for outdoor projects in medieval Scandinavia because, during the winter, the ground was covered in snow and ice, making building basically impossible. In other words, it's seriously impressive that the stone-mason is able to build the wall during the winter.
When the stone-mason begins construction of the wall, he uses his horse, Svadilfari, to move stones so large that even the gods can't believe he's doing it. The perimeter of Asgard must sure be a pretty rocky place.
Asgard also has a thick forest nearby, out of which the beautiful mare (really Loki in disguise) emerges to seduce Svadilfari away from his work. It's in that forest that Sleipnir is born. It's common in medieval stories, and in fairy tales today, for the forest to be a magical in-between place where mysterious happenings go down. Even in the world of Harry Potter, the Forbidden Forest is extra magical. When you think of it that way, it makes sense that the forest is the place where the shape-shifted Loki and Svadilfari have their fling, and where Sleipnir the magical eight-legged horse is born.
"The Walling of Asgard" fits pretty well into the category of "Deal with the Devil" legends. What a "Deal with the Devil" legend, you ask? Well, in one of those stories, a hero makes a deal with someone he might otherwise consider his enemy in order to accomplish something. Sounds a lot like the gods hiring the giant stone-mason, doesn't it?
The most famous "Deal with the Devil" story is the (originally German) legend of Dr. Faustus, who sells his soul to the devil in exchange for magical powers. That's why this type of story is also sometimes called the "Faustian Bargain."
There are lots of different kinds of deals you can make with the devil/an enemy giant, though. Let's think about some:
"Devil's Bridge" legends closely resemble "The Walling of Asgard" because of their focus big construction projects (bridges, walls – what's the difference?). Bridges built in Europe between 1000 to 1600 that are famous for their beauty or technological mastery sometimes have a folk tale associated with them that claims the devil built the bridge. In one legend, the bridge-builder promises the devil the soul of the first being to cross the bridge in exchange for his help, then cheats the devil by luring a dog across the bridge first.
Interested in reading some "Devil's Bridge" legends? You're in luck. You can find a list of stories here.
"Master Builder" legends feature a similar deal, often in exchange for the construction of a church. You can read a few of these stories here.
Because of the initially hidden identity of the stone-mason, and the fact that he is completely destroyed once his identity is unmasked, "The Walling of Asgard"is also an example of a "Name of the Helper Legend." In these legends, a mysterious stranger helps the hero accomplish a task in exchange for something very dear, but is defeated when the hero learns his identity. The most famous of these legends is "Rumpelstiltskin."
Pegasus is the winged horse in Greek and Roman mythology. Pegasus is the product of Poseidon's rape of Medusa, the snake-haired woman. On another occasion, Poseidon, like Loki, transformed himself into a horse. Poseidon's role as the horse-god might explain why his offspring with Medusa was a horse. Just like how Sleipnir is obedient to the king of the Norse gods, Pegasus is obedient to the king of the Greek gods, Zeus.
In Mythical Creatures of the North Country, author Walker Wyman tells a 19th-century lumberjack legend of a man who heard a galloping noise as he traveled through the forest. When he looked around, the man saw, but was unable to catch, a horse with eight legs positioned like a spider's. This animal was also called "Old Spider Legs." This story was part of the American lumberjack tradition of telling fantastical stories about "fearsome critters," among them the jackalope and the Jersey Devil.
Horses in medieval culture often symbolize sexuality, and Sleipnir's no exception. In fact, in "The Walling of Asgard,"we're get the details of Sleipnir's conception. His father, Svadilfari, gets so hot and bothered when he sees Loki in the form of a beautiful mare that he breaks his restraints, and the two horses share a wild night in the woods.
In Jurassic Park, the lives that find a way are monstrous man-eating dinosaurs (and some nice brontosauruses too). Sleipnir's not quite so scary, but he is sort of monstrous. His eight legs make him a mutant that's not easily categorized. This mutation probably symbolizes the character of his father, Loki, whose shape-shifting ways and position somewhere in-between god and giant make him difficult to define.
Mutant animals are often used to symbolize border-crossing and often able to help others make border-crossings that might otherwise be difficult. Sleipnir, for example, can carry his rider to the Underworld. Aragog, Hagrid's ginormous spider in Harry Potter and the Chamber of Secrets has children who hatch in the castle, leading Ron and Harry away from the safe world of Hogwarts into the dangerous, unknown world of the forbidden forest.
Mutant animals can also symbolize category transgressions (mixing of groups that don't usually mix). As much as we'd like to bring up Breaking Dawn's Renesmee as an example, what with her mutant name and non-standard parents, she's not exactly a magical animal, so we'll go back to Harry Potter. Lots of the animals Hagrid loves are mutants or combine the characteristics of several types of animals: the hippogriff is half-bird, half-horse, and his beloved dog Fluffy has three heads. Like Sleipnir, these animals have a father-figure who also defies easy categorization, for Hagrid himself is half-man, half-giant. As frightening as the mutants may be, Hagrid relates to their position in between worlds, and recognizes that this position sometimes grants the occupant unique powers.