The elves (light-elves) are often mentioned along with the Aesir, instead of the Vanir (a race of gods). The names Vanir and Alfar (light elves) may have been either synonymous, since the expression "Aesir and Alfar" meant "all the gods", or designating a difference in status between the major fertility gods, the Vanir, and the minor ones, the elves. The Van Freyr was the lord of lfheim (meaning "elvenhome"), the home of the light-elves, and he had as servants two elves: Byggvir and Beyla. Like the Vanir the elves were associated with fertility and, in late fall, the "alfablt" (elven sacrifice) was performed in the homes. It was secret, no strangers were allowed in the homes, and so next to nothing is known of it.
In Denmark the elves seem to have merged with the Huldra and are beautiful females who can dance a man to death. If you see them from the back, they are hollow.
What remained of the belief in elves in German folklore was that they were mischievous pranksters that could cause disease to cattle and people, and bring bad dreams to sleepers. The German word for nightmare, Albtraum, means "elf dream". The archaic form Albdruck means "elf pressure"; it was believed that nightmares are a result of an elf sitting on the dreamer's chest.
Little documentation exists on English rustic beliefs and terminology before the nineteenth century, but it seems that the term elf was used, at least on some occasions or in some places, for various kinds of uncanny wights, either human-sized or smaller. But other terms were also used.Post-Tolkien literary elves (popularized by the Dungeons & Dragons role-playing game) tend to be human-sized or only slightly smaller than humans, and tend also to be capable warriors, especially skilled in archery. Terms like hob or brownie or other genuine regional folklore terms are seldom used of such creatures: they are unlikely to sneak in at night and help a cobbler mend his shoes. The canonical role-playing style elf is Deedlit, a major character of the anime series Record of Lodoss War.Modern fantasy literature has revived the elves as a race distinct from fairies. Fantasy elves are different from Norse elves, but are more akin to that older mythology and to the Irish sdhe than to folktale elves.The Svartalfar live in Svartalfheim. In some sources they are identified with the dwarfs of Nidavellir, who likewise had a reputation as skilled smiths. In general, however, elves and dwarfs are distinguished in surviving Norse literature.The elves of Norse mythology have survived into folklore mainly as females. The lvor (Swedish, singular lva) were stunningly beautiful girls who lived in the forest with an elven king. They were long-lived and light-hearted in nature. They could be seen at night dancing over meadows. The circles they left were called lvdanser (elf dances) or lvringar (elf circles). If a human watched their dance, he would discover that even though only a few hours seemed to have passed, many years had passed in the real world. (This time phenomenon is retold in Tolkien's Lord of the Rings when the Fellowship of the Ring discovers that time seems to have run more slowly in elven Lothlrien. It also has a remote parallell in the Irish sdhe).