Surtr

Within Old Norse cosmology Surtr is stationed at the frontier of Múspell (Muspelheim), one of the two primordial realms said to exist before the present world (the other being Niflheim). Sources (notably the Poetic Edda's Völuspá as transmitted and the Prose Edda's Gylfaginning) present Múspell as a bright, fiery region and portray Surtr as its foremost fire-jötunn, linking him to both the primordial structure preceding the world's formation and to the eschatological return at Ragnarök when he leads Múspell's forces forth.

Surtr is described in the Eddic tradition as bearing a very bright, flaming sword; the Prose Edda specifically says his sword is "very fine" and that light will shine from it more brightly than from the sun. Accounts also state that "both before and behind him there will be burning fire" as he rides. Some manuscript readings of an Eddic stanza have been emended by editors to suggest a possible female name (Sinmara) associated with Surtr, but this identification is explicitly tentative in the sources.

Surtr's principal power is fire: he commands a martial host known as the "sons of Múspell," rides at their head at Ragnarök, and flings fire over the earth so as to burn the world. In the eschatological narrative he moves from the south, crosses (and breaks) Bifröst with his host, and is named in combat against the god Freyr (a kenning in the sources identifies Freyr as his opponent). A later euhemerizing gloss in Skáldskaparmál records an interpretation equating "Surt's fire" with historical conflagrations (e.g., the burning of Troy), but the primary Eddic and Snorric texts present him as a fated, world-consuming fiery agent.