Deadlands
Once a kingdom of thriving peoples, the lands now known as the Deadlands is a desolate waste full of the walking dead. Few dare to enter it and know to be wary near its borders. Anyone who dies within its borders rises again as an undead monstrosity, that may or may not retain its sense of self.
Long ago, the terrifying lich known as the Skull Lord took over this kingdom and created a massive army of undead, seeking to plunge the world into an undead waking nightmare. However, a group of his followers made a deal with the surrounding kingdoms to betray their master and aid a squad of heroes in defeating the lich. However, the damage was already done, and the undead still filled the land which now could not grow any life. All the heroes save one were slain in the battle, leaving the lich's ex-disciples to clean up the mess they'd helped create. They met with the neighboring kingdoms and agreed to continue to keep the dead within the borders of the Deadlands, functioning as a new nation of necromancers.
The palace in which the council of necromancers rule is known now as the Necropolis, and serves as a seat of power. Those who dwell in the Deadlands are either necromancers or undead (or both) and it dark and twisted economy of corpses and magic serves as a harsh reminder of the dangers of unleashing ancient magic upon the world.