Þrymr exists in exactly one text. Þrymskviða is his entire biography, and no other Norse source mentions him — not Snorri, not the skalds, not a kenning, not a place-name.
That is worth stating up front, because the poem he appears in is the most widely read piece of Eddic verse there is.
The demand
He is called þursa dróttinn, lord of the giants, and he has Thor's hammer. He tells Loki, who has come looking for it in a borrowed feather-cloak, that he has hidden it eight leagues under the earth and no man will get it back unless Freyja is brought to him as his wife.
He is sitting on a mound plaiting gold collars for his hounds and trimming his horses' manes when he says it. That is a superb piece of characterisation in two lines: the giant king is at home, grooming his animals, entirely relaxed, and he has stolen the one object that guarantees the gods' security.
His confidence is not misplaced in principle. The theft is well-executed and the ransom demand is standard — the giants ask for Freyja repeatedly across the corpus, and the Æsir have no way to compel him.
What goes wrong
Freyja refuses, with enough force to shake the halls. The gods hold an assembly, and Heimdall proposes dressing Thor as the bride — with linen, the necklace Brísingamen, keys jingling at his waist, a woman's dress to his knees, brooches and a headdress. Thor's objection is that the Æsir will call him unmanly, and Loki's answer is that the giants will be living in Ásgarðr shortly if he does not.
The full comic sequence belongs to Thor's own page and to the theft of the hammer. What is worth noticing here is Þrymr's part in it, because he is not a fool. He conducts his own wedding correctly. He is generous — he lists his wealth, gold-horned cattle, black oxen, treasures, and says he lacked only Freyja. He calls for the hammer to be brought in to hallow the bride, which is the correct ritual procedure at a Norse wedding, and it is his own piety that kills him.
His sister asks the bride for the bridal gift, the customary ring, and is cut down with everyone else.
Is the poem old?
This is a real and unresolved argument in Old Norse scholarship, and it matters for how the giant is read.
The traditional view treats Þrymskviða as an ancient poem — the metre is regular, the diction archaic, the story pre-Christian in outlook.
The competing view, argued forcefully in the twentieth century, is that it is a late composition, possibly thirteenth-century, written by someone who knew the Eddic corpus well and was producing a deliberate comic pastiche. The evidence adduced includes the poem's smooth, almost too-polished narrative construction, the number of phrases it shares with other Eddic poems, and a comic register that some readers find self-aware in a way the older poetry is not. The poem survives only in the Codex Regius, with no fragments or variants elsewhere.
If the late dating is right, then Þrymr is a literary invention of the Icelandic Christian period — a giant made up for a joke. If the early dating is right, he is a fossil from a genuine tradition about hammer-theft, and the ritual detail about hallowing the bride is authentic testimony about Norse weddings.
Nobody has settled it, and the Þrymskviða problem is regularly used as a teaching case for how hard Eddic dating is.
Þrymheimr is not his
A common confusion worth clearing up: Þrymheimr, the mountain hall of Þjazi that passes to Skaði, is not Þrymr's dwelling despite the similar name. The element þrymr means noise, din or clamour — appropriate for a thunder-adjacent story and for mountains, and probably the reason both names exist.
Þrymr's own hall is never named. The poem says only that he is in Jötunheimr, and the journey there takes Thor and Loki over mountains with the goats running and the earth burning.
The version everybody knows
Þrymskviða has had a durable afterlife precisely because it is funny. Icelandic rímur retold it for centuries; it has been set as opera, staged as pantomime, and adapted into children's books more often than any other Eddic poem. The image of Thor in a veil eating an entire ox is the single most reproduced comic scene in Norse mythology.
Þrymr himself has no independent life at all. He appears in games as a generic frost giant and nowhere else. For the giants as a class, see the older powers and the Norse tradition overview.
Why does a giant want Freyja specifically?
She is the standing price in these negotiations — the builder of Ásgarðr's wall asks for her along with the sun and the moon, and other giants pursue her elsewhere. The pattern is consistent enough to look structural rather than personal: the jötnar want transferred to them the things that make the gods' world habitable and fertile, and Freyja is the concentrated form of that. It is also worth noticing what the demand is not. Þrymr does not want to destroy Ásgarðr or rule it. He wants a wife of the highest available status, delivered properly, with a wedding — which makes him the most socially conventional antagonist in Norse myth.
Could a giant actually use Mjölnir?
Þrymr never tries, which is itself informative. He hides the hammer and uses it as leverage rather than as a weapon, and when he finally brings it out he does so to perform a blessing. Nothing in the poem suggests the hammer would refuse him or that he lacked the strength — the worthiness restriction familiar from modern comics has no medieval basis. The reason he does not wield it is simply that the poem is not about a fight; it is about a transaction that fails.