The paper assesses the questions if and, if yes, how the republican conception of free statehood can and should inform a compelling understanding of a legitimate post-Westphalian political order. To answer these questions, it, first, reconstructs the foundational arguments of republican internationalists in favour of free states and, second, assesses the points of contention republican cosmopolitans raise. Third, it develops an alternative approach, a republicanism of plural polities: Based on a relational and multi-dimensional understanding of citizenship, the paper questions the (...) strong internationalist reliance on the citizenship-state-nexus and on statehood in general, but also takes issue with cosmopolitans’ neglect of the boundedness of democratic self-determination. A republicanism of plural polities as a multi-perspectival approach to democratic institution-building in and beyond the state is open to constellations of plural polities of different forms and on different political levels while simultaneously recognising the particularity of each ‘free polity’. It thereby adds a new dimension to debates on the political forms legitimate institutions can assume under post-Westphalian conditions and opens avenues for research on inter-polity relations, on more complex constellations of self-rule and shared rule as well as of multilateral decision-making, on sovereignty and independence. The latter are exemplified by reference to the European context. (shrink)