Giants - Frost, Fire, and Hills of the Jotunn

The Jotunn are the giants that originate from worlds on the great world tree Yggdrasil. Jotunnheimr is the original name for the world in which Jotunn come from, with the Fire Jotunn migrating to Muspelhiem (the world of fire and lava). Frost Jotunn and Hill Jotunn live on the former world. Jotunnheimr is split into different regions of rolling hills & forests, and snow & ice-capped mountain peaks split into kingdoms of the two types of giants. The giants are each governed by a high king and they are regularly flit between war & peace with the Aesir & Vanir depending on personal grudges between individuals. They have travelled to Midgard to battle humanity regularly and have travelled far in this world, though the strongest & oldest have settled in Scandinavian lands while the younger & bravest travel outside this region to battle other peoples. Frost giants are seen as cold & calculating, never seem to rise in anger but they do, and hold grudges for eons. The hill giants are dull-witted and constantly hungry, eating almost anything they can get their hands on.
The Fire Giants left Jotunnheimr for Muspelhiem finding more to their liking. This world allows them to commune more with Surtr, the semidivine leader of fire giants, and like the world they live in, they are violent & hot-blooded, easy to anger. They endlessly wage war on all other life, when not in their forges making weapons & armour. They live like any giant, each having a clan or tribe, and having a king over each region they control, one high king is regularly elected every nine years and controls the whole of Muspelhiem. Some fire giants come to Midgard and have spread out to regions rich in metal ores to mine and send their work back to other fire giants. They have spread out across large swathes of Midgard and regularly try to take over other giant territory.
Many different species try to make peace with these giants, though Germanic peoples seem to have the greatest chance to. This seems to be cultural in origin, with both sides having an idea of how the others view the worlds around them. A few can be found serving Elves or Dwarves too, or vice versa, again being cultural.