Élivágar in the context of Gjöll

In Norse mythology, Ymir (/ˈiːmɪər/), also called Aurgelmir, Brimir, or Bláinn, is the ancestor of all jötnar. Ymir is attested in the Poetic Edda, compiled in the 13th century from earlier traditional material, in the Prose Edda, written by Snorri Sturluson in the 13th century, and in the poetry of skalds. Taken together, several stanzas from four poems collected in the Poetic Edda refer to Ymir as a primeval being who was born from atter (Old Norse: eitr), yeasty venom that dripped from the icy rivers called the Élivágar, and lived in the grassless void of Ginnungagap. Ymir gave birth to a male and female from his armpits, and his legs together begat a six-headed being. The grandsons of Búri, the gods Odin and Vili and Vé, fashioned the Earth—elsewhere personified as a goddess named Jörð—from Ymir's flesh; the oceans from his blood; from his bones, the mountains; from his hair, the trees; from his brains, the clouds; from his skull, the heavens; and from his eyebrows, the middle realm in which humankind lives, Midgard. In addition, one stanza relates that the dwarfs were given life by the gods from Ymir's flesh and blood (or the Earth and sea).

In the Prose Edda, a narrative is provided that draws from, adds to, and differs from the accounts in the Poetic Edda. According to the Prose Edda, after Ymir was formed from the elemental drops, so too was Auðumbla, a primeval cow, whose milk Ymir fed from. The Prose Edda also states that three gods, the brothers Odin, Vili and Vé, killed Ymir, and details that, upon Ymir's death, his blood caused an immense flood. Scholars have debated as to what extent Snorri's account of Ymir is an attempt to synthesize a coherent narrative for the purpose of the Prose Edda and to what extent Snorri drew from traditional material outside of the corpus that he cites. By way of historical linguistics and comparative mythology, scholars have linked Ymir to Tuisto, the Proto-Germanic being attested by Tacitus in his 1st century CE ethnography Germania and have identified Ymir as an echo of a primordial being reconstructed in Proto-Indo-European mythology.

Aurvandill (Old Norse) is a figure in Germanic mythology. In Norse mythology, the god Thor tosses Aurvandill's toe – which had frozen while the thunder god was carrying him in a basket across the Élivágar rivers – into the sky to form a star called Aurvandils-tá ('Aurvandill's toe'). In wider medieval Germanic-speaking cultures, he was known as Ēarendel in Old English, Aurendil in Old High German, Auriwandalo in Lombardic, and possibly as 𐌰𐌿𐌶𐌰𐌽𐌳𐌹𐌻 (auzandil) in Gothic. An Old Danish Latinized version, Horwendillus (Ørvendil), is also the name given to the father of Amlethus (Amleth) in Saxo Grammaticus' Gesta Danorum.

Comparative studies of the various myths where the figure is involved have led scholars to reconstruct a Common Germanic mythical figure named *Auza-wandilaz, meaning 'light-beam' or 'ray of light'. According to the Old English and Gothic sources, and to a lesser degree the Old Norse text (where a star is mentioned without additional details), this figure seems to have personified the 'rising light' of the morning, possibly the Morning Star (Venus). However, the German and Old Danish evidence remain difficult to interpret in this model.