Empire
An empire is a "political unit" made up of several territories and peoples, "usually created by conquest, and divided between a dominant center and subordinate peripheries". The center of the empire exercises political control over the peripheries. Within an empire, there is non-equivalence between different populations who have different sets of rights and are governed differently. Narrowly defined, an empire is a sovereign state whose head of state is an emperor; but not all states with aggregate territory under the rule of supreme authorities are called empires or ruled by an emperor; nor have all self-described empires been accepted as such by contemporaries and historians. There have been "ancient and modern, centralized and decentralized, ultra-brutal and relatively benign" Empires.
