Athas

Athas is a strange pseudo-kingdom. Rather than a single kingdom, it is actually composed of several city-states, ruled over by the tyrannical Sorcerer Kings. The Grey Wastes, as it is known by the outside world, has no real leader, but instead a strange web of pseudo-alliances between the various city states. These alliances are constantly shifting, but there is a single grave rule which they all adhere to religiously; Nobody escapes. Whether through killing, magic, or other means, nobody escapes Athas.

This rule isn't perfectly enforced (It's basically impossible to control an entire population) and so the occasional Athasian escapes the Grey Wastes, though so few that nobody is quite sure if their apocalyptic tales are true.