Since colonization and throughout the independence period, ethnic iden- tity has played a major role in the politics and conflicts of the Democratic Republic of Congo. This report investigates how issues of ethnic identity intersect with politics and conflicts in eastern Congo, and particularly Kalehe territory and on Idjwi Island, South Kivu Province. It demonstrates that these connections are anchored in long-term historical processes. We make two main points: First, we argue that colonial policies of ethnic territorialization and indirect rule have strongly shaped today’s politics of identity and terri- tory in eastern Congo. We show how colonial policies of ethnic territoriali- zation and indirect rule changed the means and ends of political authority in eastern Congo in profound ways. The overall effect of these policies was that the purpose of political authority gradually pivoted towards the extrac- tion and accumulation of resources, the capture and amassing of authority, and ensuring the support of state authorities. Furthermore, we argue that, in the long run, the idea of ethnic territories came to shape how elites and the masses understood politics and its stakes in Congo, resulting in ideas of ethnic identity and territory becoming more salient in political struggles. Second, we argue that the colonial legacy of resource accumulation, eth- nic territorialization, and the concentration of authority has produced an inequitable and fragmented political order, which is conducive to conflict. As a result, our main recommendation is that a fundamental reckoning with the most destructive legacies of Congo’s colonial legacy – resource extraction, the centralization of authority, and ideas about bounded and homogenous ethnic identities – should be a main priority of the efforts of the people of Congo to establish a sustainable political order.