Notes from my current Pathfinder game setting, 'Bretharis'
Five centuries ago, a band of adventurers united the land in defence of civilisation against the forces of evil and corruption.
Their human leader was hailed as high king and his lineage became the balancing force between each of the nations of the continent.
Three decades ago the final high king died without a clear heir, spawning a war between nations over who would ascend the throne.
From the ashes of war three powers emerged, one monarchy, one theocracy, and one arcane oligarchy, which consumed their rivals.
A fourth underground faction composed of common folk under the influence of a charismatic leader currently seeks to bring forth democracy instead.
Thirty years of warfare has seen civilisation crumble in many areas as the fields of fallen feed hordes of monsters.
Many of those who have lost their homes, families and entire way of life have become easy fodder for cults promising revenge on their oppressors.
Slavery is widespread and highly profitable within the theocracy, though slaves are offered release from servitude after five years if they convert.
Necromancy is common within the arcane oligarchy, with undead serving as endless power sources inside the gears of massive constructions.
Several rifts exist within the world to hellish planes, where bastions of the forces of good wage endless war to hold off the tide of evil.