Jörmungandr: What the Norse Sources Say About the Midgard Serpent

Jörmungandr, the Midgard Serpent, is the monster that holds the Norse world together by lying around it — and the one Thor is fated to kill and die beside. Most of what is repeated about it online comes from one thirteenth-century book. Some of the best-known lines come from nowhere at all. This is what the sources actually say, who wrote them, and where they disagree.

Who Jörmungandr is — and who wrote it down

The fullest account sits in Gylfaginning, the first part of the Prose Edda, written in Iceland around 1220 and credited to Snorri Sturluson. In chapter 34, Snorri introduces three siblings. In Arthur Gilchrist Brodeur's 1916 translation, the one published by the American-Scandinavian Foundation in New York and still the standard public-domain English version:

"Angrboda was the name of a certain giantess in Jötunheim, with whom Loki gat three children: one was Fenris-Wolf, the second Jörmungandr—that is the Midgard Serpent,—the third is Hel."

The gods learn by prophecy that the three will bring disaster, and Odin has them brought to him. The wolf is kept among the gods and eventually bound — his story is told in our piece on Fenrir. Hel is sent down to rule the dead. The serpent goes into the sea:

"straightway he cast the serpent into the deep sea, where he lies about all the land; and this serpent grew so greatly that he lies in the midst of the ocean encompassing all the land, and bites upon his own tail."

That is nearly the whole origin story. Everything else about Jörmungandr happens in relation to Thor.

The name is worth a moment. Gandr is a slippery Old Norse word that can mean a staff, a magical object or a monster; jörmun- is an intensifying element meaning something like "vast" or "mighty," found in other old Germanic names. The usual rendering is "the huge monster" or "the mighty staff." Snorri himself glosses it straight away with the everyday name: Miðgarðsormr, the serpent of Midgard — Midgard being the "middle enclosure," the world of humans. The serpent is named after the thing it surrounds.

The tail in its mouth — and the line nobody wrote

Snorri says the serpent bites its own tail. He says it once more, indirectly, in the episode at Útgarða-Loki's hall, where the giant tells Thor the cat he tried to lift "was the Midgard Serpent, which lies about all the land, and scarcely does its length suffice to encompass the earth with head and tail." The picture is consistent: a body long enough to go around the world, only just.

What you will not find in any medieval source is the sentence that fills posters and tattoo captions: when Jörmungandr lets go of its tail, Ragnarök begins. Neither Snorri nor the poems of the Poetic Edda say it. At Ragnarök the serpent rises, the sea floods the land and it comes ashore — but no text ties that moment to the tail. The line is a modern extrapolation, and a neat one, which is probably why it spread.

The folklorist John Lindow reads the tail-biting differently: not as a clock waiting to run out, but as one more example of a pattern that runs through Norse myth — the bound monster. Fenrir is chained, Loki is tied to rocks, and the serpent is held in place by its own body. All of them are contained rather than destroyed, and all of them get loose at the end. That is an interpretation, clearly labelled as one, but it fits the sources better than the poster version does.

Three meetings with Thor

Across Snorri's text, Thor and the serpent meet three times. Each meeting is bigger than the last, and only the third is final.

Meeting	Where it is told	What happens	Outcome
The cat	Gylfaginning 46–47	At Útgarða-Loki's hall Thor is set to lift a grey cat and manages only one paw. It was the serpent in disguise.	A draw — and a fright for the giants
The fishing trip	Gylfaginning 48; Hymiskviða; skaldic poems	Thor rows out with the giant Hymir, baits a hook with an ox head and hauls the serpent to the gunwale.	Disputed (see below)
Ragnarök	Völuspá; Gylfaginning 51	The serpent comes ashore spewing venom. Thor kills it.	Thor walks nine paces and falls dead

The cat that was a serpent

The first meeting is a trick. Thor, travelling in the lands of the giants, is humiliated in a series of contests at Útgarða-Loki's hall: he loses an eating match, fails to drain a drinking horn, cannot lift a cat off the floor. Only the next morning does the giant admit that everything was illusion. The horn was connected to the sea. The cat was the Midgard Serpent, and when Thor raised one of its feet from the floor, the serpent had been lifted almost to the sky. Everyone who saw it, the giant says, was afraid.

The fishing trip

The second meeting was clearly the favourite of Viking-age poets and carvers. Thor, disguised as a young man, stays with the giant Hymir and asks to go fishing with him. Told to find his own bait, he tears the head off Hymir's largest ox. They row out further than Hymir likes — the giant warns it is dangerous because of the Midgard Serpent — and Thor casts the ox head overboard on a strong line. In Brodeur's translation: "The Midgard Serpent snapped at the ox-head, and the hook caught in its jaw." The serpent pulls so hard that Thor's fists crash against the gunwale. Thor braces himself with divine strength until his feet go through the bottom of the boat and he stands on the sea floor, and he drags the serpent up to the side.

Snorri lingers on the moment: Thor glaring at the serpent, the serpent staring back and spitting venom, Hymir turning pale as the sea pours into the boat. Then, just as Thor raises his hammer, the terrified giant cuts the line.

Ragnarök: nine paces

The third meeting settles it. Völuspá, the great poem of the world's beginning and end, gives the serpent a single vivid line as the end begins — in R. B. Anderson's 1880 rendering of the stanza as Snorri quotes it: "Jormungand welters / In giant rage / And smites the waves." Snorri turns the poem into prose: the sea rushes over the land as the serpent seeks the shore; it blows venom that fouls the air and the sea; it takes its place beside the wolf. Then, in Anderson's translation: "Thor gets great renown by slaying the Midgard-serpent, but retreats only nine paces when he falls to the earth dead, poisoned by the venom that the serpent blows on him."

The strongest god in the pantheon wins his last fight and dies of it nine steps later. That symmetry — neither survives the other — is the heart of the story.

Did Thor kill the serpent on the fishing trip?

Here the sources genuinely split, and Snorri tells us so himself. After Hymir cuts the line and the serpent sinks, Thor hurls his hammer after it. Brodeur's translation: "men say that he struck off its head against the bottom; but I think it were true to tell thee that the Midgard Serpent yet lives and lies in the encompassing sea."

That sentence is unusual. The narrator of Gylfaginning admits there is another version in circulation and rejects it — because if the serpent died in the fishing trip, it could not fight Thor at Ragnarök. The alternative did exist. Húsdrápa, composed around 985 by the Icelandic poet Úlfr Uggason to describe carved panels in a hall at Hjarðarholt, contains a stanza that scholars usually read as Thor striking the serpent's head off among the waves. The older Ragnarsdrápa, attributed to the ninth-century poet Bragi Boddason and describing images on a painted shield, also includes the fishing scene.

The Eddic poem Hymiskviða takes a middle road. It calls Thor orms einbani, the serpent's "lone slayer," while baiting the hook — an epithet that looks forward to Ragnarök — and has him strike the monster's head with his hammer before, in most readings, it sinks back into the sea. The simplest summary: there were at least two endings to the fishing story in the Viking age, and Snorri chose the one that kept his larger timeline intact.

The serpent in stone: Altuna, Hørdum, Gosforth

The fishing trip is the one Norse myth we can see across the Viking world in stone, which makes it unusually good evidence that the story was widely known before anyone wrote it down.

• Altuna, Sweden (U 1161). An eleventh-century runestone in Uppland shows a figure in a boat with a hammer raised, an ox head on the line and a serpent below — and one foot pushed through the bottom of the boat, exactly Snorri's detail. Hymir is not shown. The stone is a memorial, raised by three brothers for their father Holmfastr and for Arnfastr; the inscription indicates that both were burned.
• Hørdum, Denmark. A carved stone from Thy in northern Jutland shows the same scene: a boat, a line, and a foot braced through the planks.
• Gosforth, England. In St Mary's Church in Gosforth, Cumbria, a carved stone of the tenth century shows two figures in a boat with an ox head as bait. It stands beside the famous Gosforth Cross, whose reliefs are widely read as Ragnarök scenes placed on a Christian monument.

A fourth example, the Gotland picture stone Ardre VIII, is sometimes said to show the fishing trip as well. The identification is plausible but not certain, and it should be treated that way.

For American readers, Gosforth is a reminder that Norse myth was not only Scandinavian. It travelled with settlers into northern England, where it was carved beside the Crucifixion by people who apparently saw no contradiction in telling both stories at once.

A medieval author explains the myth away

One of the strangest texts about the serpent is also one of the least quoted. In an afterword that opens Skáldskaparmál, the second part of the Prose Edda, the author warns young poets that "christian men should not believe in heathen gods," and then explains where the old stories came from: the Æsir were men from Troy who retold the Trojan War as myth. The fishing trip gets a specific explanation, in Anderson's translation:

"When it is said that Oku-Thor angled with an ox-head and drew on board the Midgard-serpent, but that the serpent kept his life and sank back into the sea, then this is another version of the story that Hektor slew Volukrontes, a famous hero, in the presence of Achilleus…"

The passage goes on to map Ragnarök onto the fall of Troy. As history it is worthless. As evidence it is priceless: it shows a Christian Icelandic writer in the thirteenth century, fond of the old stories and needing a respectable reason to keep them. Whether Snorri wrote this section himself is debated. Either way, it is a reminder that the Prose Edda is a learned medieval book about myth, not a pagan scripture.

Leviathan, Indra and the ouroboros: what comparisons can prove

Three comparisons come up again and again. Each is interesting; none proves as much as it is often asked to.

Leviathan. The Book of Job asks, in the King James wording, "Canst thou draw out leviathan with an hook?" The image of a god fishing for a sea monster was available to Christian readers in the medieval North, and some scholars have asked whether the Christian tradition shaped how the Thor story was told or carved. But the fishing trip already appears in skaldic poetry that most scholars place before or around the conversion. Influence on details is possible; borrowing of the whole story is not demonstrated.

Indra and the dragon. The linguist Calvert Watkins, in How to Kill a Dragon (Oxford University Press, 1995), traced a very old Indo-European formula of a hero or storm god slaying a serpent, with the Vedic god Indra and the serpent Vṛtra as a classic example. Thor and Jörmungandr fit the family resemblance. The Danish scholar Preben Meulengracht Sørensen read the fishing trip in terms of cosmic balance: the serpent is dangerous but also part of the order that holds the world together. These are scholarly frameworks, not facts about what Viking-age people believed.

The ouroboros. A serpent biting its tail inevitably invites comparison with the ouroboros of Egyptian and alchemical tradition. The shape matches; the meaning mostly doesn't. The ouroboros in alchemy stands for unity and self-renewal, while Jörmungandr is a hostile force held in place. Whether the Norse image owes anything to the Mediterranean one is unknown. Our article on the ouroboros traces that symbol on its own terms, and the Yggdrasil piece describes the cosmos the serpent encircles.

Where the popular version walks past the evidence

Marvel's Thor comics and the 2018 video game God of War did more to make Jörmungandr famous in the United States than any edition of the Eddas. Neither is trying to be a source, and there is nothing wrong with that. The trouble starts when details from retellings flow back into "what the Vikings believed." Three common ones, checked:

• "Ragnarök begins when it releases its tail." Not in any medieval source.
• "Jörmungandr was a guardian or protector of Midgard." Not in the sources, which present it as the gods' enemy. Lindow's "bound monster" reading comes closest, and even there the point is containment, not protection.
• "The serpent was worshipped." There is no record of any cult, prayer or offering to Jörmungandr. For a symbolic reading of snakes more generally, see snake symbolism — a different subject from the Norse monster.

Frequently asked questions

Who is Jörmungandr in Norse mythology?

Jörmungandr, also called the Midgard Serpent, is one of the three children of Loki and the giantess Angrboda, alongside Fenrir and Hel. Odin cast it into the sea, where it grew until it encircled the world and bit its own tail. It is Thor's great enemy and the two kill each other at Ragnarök.

What does the name Jörmungandr mean?

It combines jörmun-, an intensifier meaning something like "vast" or "mighty," with gandr, a word that can mean a staff, a magical object or a monster. "The huge monster" is a fair rendering. Snorri glosses it at once as the Midgard Serpent, the serpent of the human world.

Does Ragnarök begin when Jörmungandr lets go of its tail?

Not according to any medieval source. The Prose Edda says the serpent bites its tail, and that at Ragnarök it rises, floods the land and comes ashore. The idea that releasing the tail triggers the end is a modern addition.

How does Thor kill Jörmungandr?

At Ragnarök Thor kills the serpent, walks nine paces and falls dead from the venom it has blown on him. That is Snorri's account, built on the poem Völuspá. Whether Thor had already killed it on his fishing trip is disputed: Snorri reports that some said so and rejects it.

What happened when Thor went fishing for the Midgard Serpent?

Thor rowed out with the giant Hymir, used an ox head as bait and hooked the serpent. He braced so hard his feet went through the boat, and hauled the serpent to the side. As he raised his hammer, Hymir cut the line and the serpent sank back into the sea.

Is Jörmungandr the same as the ouroboros?

The shape is the same, a serpent biting its tail, but the meaning differs. The alchemical ouroboros stands for unity and renewal; Jörmungandr is a hostile force held in place until the end of the world. Whether the Norse image borrowed from the Mediterranean one is unknown.

Sources

• Snorri Sturluson, Prose Edda: Gylfaginning 34, 46–48 and 51, translated by Arthur Gilchrist Brodeur (American-Scandinavian Foundation, New York, 1916; public domain); and the complete translation by Rasmus B. Anderson, The Younger Edda (1880; Project Gutenberg), including Völuspá as quoted by Snorri and the afterword to Bragi's talk in Skáldskaparmál. The standard scholarly edition is Anthony Faulkes', published free by the Viking Society for Northern Research.
• Hymiskviða and Völuspá, Poetic Edda (Codex Regius, 13th century).
• Úlfr Uggason, Húsdrápa (c. 985), and Bragi Boddason, Ragnarsdrápa (9th century), as preserved in Skáldskaparmál.
• Scandinavian Runic-text Database (Rundata), U 1161 (Altuna), Uppsala University.
• John Lindow, Norse Mythology: A Guide to the Gods, Heroes, Rituals, and Beliefs (Oxford University Press, 2001), entries on the Midgard Serpent and Thor.
• Preben Meulengracht Sørensen, "Thor's Fishing Expedition," in G. Steinsland (ed.), Words and Objects (Oslo, 1986).
• Calvert Watkins, How to Kill a Dragon: Aspects of Indo-European Poetics (Oxford University Press, 1995).
• Job 41:1, King James Version.
• Rudolf Simek, Dictionary of Northern Mythology (D. S. Brewer, 1993).