The Fourth Imperium
Ravenloft is an extraplanar prison used by the Imperium Unitas.
Ravenloft holds the world’s worst kind of prisoners, and then some. While it is the type of place that immortal dread lords are sent to, a political revolutionary could also quickly find his way behind the five feet thick stone walls.
It is said that Ravenloft is inescapable. Few men have ever even gotten out of the castle, and no one is certain about what happened to the few that did. Surrounding Ravenloft are miles of ocean as far as the eye can see. Beyond that? That’s a question for your local politician to dodge.
Within the walls of Ravenloft, the entire castle is enchanted to dispel magic. The enchantment is so powerful that it is sometimes said to wipe undead lich lords from existence. Due to this, prisoners are virtually given free roam around the castle during the day. This results in daily murders, riots, escape attempts that the High Senate has often called “population control.”