In Norse mythology, the Norns (pronounced like “norms” with an “n” instead of the “m”; Old Norse Nornir) are female beings who create and control fate. This makes them the most terribly powerful entities in the cosmos – more so than even the gods, since the gods are subject to fate just like any and all other beings.
According to one description of the Norns in the Old Norse poem Fáfnismál, there are a great many of them, and no one knows the exact number. Some of them come from the gods, others from the elves, and still others from the dwarves. The poem Völuspá, however, has another, grander account of them that has (perhaps deservedly) become the standard image that people today associate with the Norns.
In Völuspá, the Norns are mysterious beings who don’t seem to come from any of the recognized kinds of beings who populate the Norse otherworld. They seem to be a category unto themselves. There are exactly three of them, and their names suggest their ability to construct the content of time: one is Urd (Old Norse Urðr, “The Past,” and a common word for fate in and of itself), the second Verdandi (Old Norse Verðandi, “What Is Presently Coming into Being”) and the third Skuld (Old Norse Skuld, “What Shall Be”). They live in a hall by a well (Urðarbrunnr, “Well of Fate”) beneath Yggdrasil, the mighty tree at the center of the Norse otherworld, which holds the Nine Worlds in its branches and roots.
Several different images are used for the Norns’ fate-crafting activity throughout Old Norse literature. The three most common are casting wooden lots, weaving a piece of cloth, and carving symbols – likely runes – into wood.
There’s no evidence that the Norns were ever worshiped. A person lamenting his or her fate is a relatively common element in Old Norse literature, and in ancient and medieval Germanic literature more broadly, so we can be sure that if the Vikings had thought it possible to productively petition the Norns to change their fates, they would have. But in the Norse view, fate was blind and utterly implacable. You couldn’t change it; all that was left to you was to decide the attitude with which you would meet whatever fate happened to bring.
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 The Poetic Edda. Fáfnismál, stanza 13.
 The Poetic Edda. Völuspá, stanza 20.
 Price, Neil. 2002. The Viking Way: Religion and War in Late Iron Age Scandinavia. p. 56.
 Davidson, H.R. Ellis. 1988. Myths and Symbols in Pagan Europe: Early Scandinavian and Celtic Religions. p. 164.