Landvaettir

Landvaettir (singular landvaettur), or landwights, are the sentient humanoid species besides humankind created by the gods of the Aesir and Vanir to inhabit Midhgardhur and the Nine Worlds. They are sometimes called demihumans, since from a human perspective they seem almost, but not quite, human-like. The landvaettir of Midhgardhur include (but are not necessarily limited to) alfar ("elves"), dvergar ("dwarves"), lytlingar ("littlings" or "halflings"), and huldrufolk ("hidden folk" or "gnomes"). Some of these have their own worlds (the world of Alfheimur granted to the alfar by the Vanir, for example), some have lost their worlds (e.g. the dvergar, lytlingar, and huldrufolk once dwelt in a realm called "Myrkheimur" which has since become the world of Svartalfaheimur), and some landvaettir have even become corrupted by the Jotnar, like the svartalfar.

Some of the Northern faith believe that the souls of human dead can sometimes achieve reincarnation rather than dwelling forever in the halls of the gods, and that reincarnated souls sometimes become landvaettir rather than humans.

Source: The landvaettir in traditional Norse myth are spirits of the land and nature. Author Colin Anders Brodd created the landvaettir of Midhgardhur based on the "demihuman" races of traditional fantasy role-playing games, who are often supposed to be closer to the land (often: dwarves to stone and caverns, elves to trees and forests, halflings to cultivated lands and fields, gnomes to hidden places in the hills, forests, and wilderness). He wrote: "I wanted to be able to work into the Midhgardhur stories the concept of fantasy 'races' like in FRPGs (Fantasy Role-Playing Games), but I wanted them to also have a solid basis in Norse folklore and mythology. Thus, I set mine up as land-wights, using traditional Norse names of alfar elves and dvergar dwarves, reassigning the fairy-like huldrufolk as gnomes, and creating lytlingar halflings whole cloth, as Tolkien and writers since him have done, from common legends of human-like 'little people'. It involved some creative juggling of the myths from the sources, but I think it works."