An elf (Old Norse álfr, Old English ælf, Old High German alb, Proto-Germanic *albaz) is a certain kind of demigod-like being in the pre-Christian mythology and religion of the Norse and other Germanic peoples.
The elves are luminous beings, “more beautiful than the sun,” whose exalted status is demonstrated by their constantly being linked with the Aesir and Vanir gods in Old Norse and Old English poetry. The lines between elves and other spiritual beings such as the gods, giants, dwarves, and land spirits are blurry, and it seems unlikely that the heathen Germanic peoples themselves made any cold, systematic distinctions between these various groupings. It’s especially hard to discern the boundary that distinguishes the elves from the Vanir gods and goddesses. The Vanir god Freyr is the lord of the elves’ homeland, Alfheim, and at least one Old Norse poem repeatedly uses the word “elves” to designate the Vanir. Still, other sources do speak of the elves and the Vanir as being distinct categories of beings, such that a simple identification of the two would be misguided.
The elves also have ambivalent relations with humans. Elves commonly cause human illnesses, but they also have the power to heal them, and seem especially willing to do so if sacrifices are offered to them. Humans and elves can interbreed and produce half-human, half-elfin children, who often have the appearance of humans but possess extraordinary intuitive and magical powers. Humans can apparently become elves after death, and there was considerable overlap between the worship of human ancestors and the worship of the elves.
The worship of the elves persisted centuries after the Germanic people’s formal conversion to Christianity, as medieval law codes prohibiting such practices demonstrate. Ultimately, then, their veneration lasted longer than even that of the gods.
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 Orel, Vladimir. 2003. A Handbook of Germanic Etymology. p. 13.
 Snorri Sturluson. The Prose Edda. Gylfaginning 17.
 Turville-Petre, E.O.G. 1964. Myth and Religion of the North: The Religion of Ancient Scandinavia. p. 231.
 The Poetic Edda. Grímnismál, stanza 5.
 Hall, Alaric. 2007. Elves in Anglo-Saxon England. p. 36.
 Turville-Petre, E.O.G. 1964. Myth and Religion of the North: The Religion of Ancient Scandinavia. p. 232.
 Kormáks saga.
 Þiðreks saga.
 Hrólfs saga kraka.
 The Poetic Edda. Völundarkvíða.
 Óláfs Saga Helga. In Flateyjarbók.