Roman citizenship was, for most of Roman history, a restricted status that conferred concrete legal advantages and carried genuine political weight. It was also, uniquely among ancient states, something Rome was willing to extend — gradually, pragmatically, and eventually universally — in a process that transformed a city-state’s civic identity into the legal framework of a multinational empire. The story of Roman citizenship is the story of how Rome absorbed the world it conquered without ceasing, at least formally, to be Rome.