In the Edda, we’re told of the nine dimensions: Asgard (Aesir, the land of the gods), Alfheim (land of the light elves), Vanaheim (land of the Vanir), Midgard (the land of men), Jotunheim (the land of ice giants), Svartalfheim (land of the dark-elves), Nidavellir (land of the dwarves), Muspelheim (land of the fire spirits), and Niflheim (the land of the dead).
Nidavellir, the home of the dwarves, is a realm of darkling worlds, populated by humanoid creatures, short of stature, but very strong. Naturally good at crafting, they love treasures and the rare metals; when young, they go exploring for new materials as part of their transition to adulthood. These walk-abouts can last hundreds of years; they are forbidden to marry until they have brought a new element, gem or building technique back to their clan.
Masters of metal work and stone craft, they were the architects and builders of the great wonders of the ancient world. They know rune-magic for building that no other races can master. Before the fall, they traveled between the nine realms, working for the rulers of those places on public works and private palaces.
As a race, they are long-lived and very hearty. It takes effort to kill a dwarf! They are not particularly warlike, preferring the role of merchant when they are not building. However, they are fierce in their protection of their territories and have gone to war when those strong-holds were threatened.
Slow to anger, they make stalwart companions and worse enemies, as they never forget a slight and can hold a grudge for eons.