This article explores the migrations of Turkish Muslims after the 1878 Peace Treaty of Berlin, which severed much of the Balkans from the Ottoman Empire as fully independent nation-states or as nominally dependent polities in the borderlands of the empire. I focus on one such polity—the administratively autonomous Ottoman province of Eastern Rumelia—which, in wrestling to reconcile liberal principles of equality and political representation understood in ethno-religious terms, prompted emigration of Turkish Muslims while enabling Bulgarian Christian hegemony. Scholars have studied Muslim emigration from the Balkans as the Ottoman Empire gradually lost hold of the region, emphasizing deleterious effects of nationalism and aggressive state-building in the region. Here I look at migration at empire's end, and more specifically at the management of migration as constitutive of sovereignty. The Ottoman government asserted its suzerainty by claiming to protect the rights of Eastern Rumelia's Muslims. The Bulgarian dominated administration of Eastern Rumelia claimed not only administrative but also political autonomy by trying to contain the grievances of Turkish Muslims as a domestic issue abused by ill-meaning outsiders, all the while insisting that the province protected the rights of all subjects. Ultimately, a “corporatist” model of subjecthood obtained in Eastern Rumelia, which fused the traditional religious categorization of Ottoman subjects with an ethnic one under the umbrella of representative government. The tension between group belonging and individual politicization that began unfolding in Eastern Rumelia became a major dilemma of the post-Ottoman world and other post-imperial societies after World War I.