When Kosovo declared its independence in 2008, it did so not as a nation-state, but as a “state of communities,” self-defining as multiethnic, diverse, and committed to extensive rights for minorities. In this paper, this choice is understood as a response to a dual legitimation problem. Kosovo experienced both an external legitimation challenge, regarding its contested statehood internationally, and an internal one, vis-à-vis its Serb minority. The focus on diversity and minority rights was expected to confer legitimacy on the state both externally and internally. International state-builders and the domestic political elite in post-conflict Kosovo both pursued this strategy. However, it inadvertently created an additional internal legitimation challenge, this time from within Kosovo's majority Albanian population. This dynamic is illustrated by the opposition movement “Lëvizja Vetëvendosje” (Self-Determination Movement), which rejects the framing of Kosovo as first and foremost a multiethnic state. The movement's counter-narrative represents an additional internal legitimation challenge to the new state. This paper thus finds that internationally endorsed “diversity management” through minority rights did not deliver as a panacea for the legitimacy dilemmas of the post-conflict polity. On the contrary, the “state of communities” continues to be contested by both majority and minority groups in Kosovo.