The realms of the Norse deities were separated into the Nine Worlds, nine different dimensions of reality which the deities utilized as their stomping grounds. The Nine Worlds of Norse mythology included:
Asgard, home of the gods, and original home of the Aesir, ruled by Odin and Frigga.
Vanaheim, original home of the Vanir, ruled in the past by Freya and Frey.
Jotunheim, home of the giants, or Jotuns; the Frost Giants (who inhabit the frozen tundra of this reality, and who depend upon very cold temperatures to exist) are ruled by Utgard-Loki; the Storm Giants (who inhabit the mountainous regions of this realm) are ruled by Thrym.
Niflheim, former home of the frost giants and once ruled by Ymir, and now realm of the dishonored dead, ruled by Hela (the honored dead go to Valhalla, a special part of Asgard overseen jointly by Odin and Freya). The realm is guarded by the dragon Nidhogg.
Hel (or Helheim; not to be confused with the Christian afterlife realm of punishment known as “Hell”), land of the common dead, also ruled by Hela (and in which she obviously named after herself).
Muspelheim, land of the fire demons, or Muspeli(sometimes described as giants or elementals), ruled by Surtur.
Alfheim, land of the Light Elves (the Norse name for the faerie folk, or fays), ruled in ancient times by Frey but now guarded by the elf Delling (according to author Freya Aswynn).
Svartalfheim, land of the Dark Elves (some of whom were known in Western folklore as goblins), ruled by the dark elf Modsognir (also according to Freya Aswynn).
Midgard (Earth), the material manifested world of humanity, whose official guardian is Thor, though he obviously doesn’t rule this dimension of reality per se.
Each of the Nine Worlds are connected to each other by the roots of the cosmic ash tree called Yggdrasil. Asgard itself is dimensionally connected to Earth by a rainbow hued bridge called Bifrost, which is guarded by the god Heimdall.
