Valkyrja in Old Norse means, very literally, 'chooser of the slain'. They are Odin's shield-maidens — a host of female spirits who ride above every battlefield in the nine worlds and decide, with the cool eye of someone for whom death is administration, which warriors will fall and which will be carried back to Valhalla to fight again at the end of the world.
The Eddas and the sagas describe them in two registers, and you have to hold both at once. In one, they are radiant women in burnished mail, helms of gold, spears flashing, riding white horses across the storm — and the northern lights themselves are said to be the gleam of their armour against the clouds. In the other, older register, they are far more frightening: war-spirits in raven shape, drinking from skulls on the battlefield, weaving the fates of men on a loom strung with human entrails. Both pictures are true. The Norse never softened them.
There are named ones — Brynhildr, Sigrún, Hildr, Þrúðr, Hlökk, Geirahöð, and a dozen more — and the most famous of them is Brynhildr, the Valkyrie punished by Odin for choosing the wrong warrior to die. He pricks her with a sleep-thorn and lays her on a mountain ringed with fire until a hero brave enough to ride through the flames comes to wake her. The hero is Sigurðr, who has just killed the dragon Fáfnir. Their love story ends in betrayal, magic potions, mistaken identity and a funeral pyre big enough for both of them. Wagner wrote four operas about it. The Norse needed only one song.
The Valkyries' real job is selection. Half of the slain go to Freyja, who claims the first pick for her hall Fólkvangr; the other half go to Odin in Valhalla, where they feast every night and fight every day in preparation for Ragnarök. The Valkyries serve the mead. They also pour it. The same hand that lifted you off the battlefield refills your horn at the long table — and it is meant to be a kindness.
Christianity arrived in Scandinavia and did its best to demote them — into angels, into ghosts, into demonic seductresses — but the older shape kept surfacing. The Valkyrie is the Norse acceptance that death in battle is not random. Somebody chooses. And when you fall, somebody comes for you.
Wear the Valkyrie and you wear the Old Norse promise — that the storm above the battlefield is not empty, that the aurora is armour, and that the one who carries you off the field at the end is a woman with a spear, riding very fast.