Secret Masters — The world is actually run by a hidden cabal, acting through their catspaws in the visible government. For one reason or another, this group finds it imperative that they not be identified by outsiders, and in some cases even the planet’s own government may not realize that they’re actually being manipulated by hidden masters.
Theocracy — The planet is ruled by the priesthood of the predominant religion or ideology. The rest of the locals may or may not be terribly pious, but the clergy have the necessary military strength, popular support or control of resources to maintain their rule. Alternative faiths or incompatible ideologies are likely to be both illegal and socially unacceptable.