Critical environmental approaches to renewable energy have identified the creation of new resource frontiers as a problematic aspect of energy transition efforts, especially in the Global South where utility-scale projects often dispossess already marginalized residents. However, these frontiers usually emerge in peripheries that had already been constituted as “new” resource frontiers during colonial incorporation into global capitalism. This paper examines one historical moment in the creation of resource frontiers in southeastern Morocco as laying the bureaucratic, juridical, and political framework for contemporary reappropriations of land and other natural resources in the service of renewable energy. Specifically, I review internal debates within the French colonial administration about how to simultaneously facilitate and control mining in the zones of the Protectorate that had not yet or were in the process of coming under French military control. The archives of the Service des Mines and Bureau de Recherche et Participations Minières reveal considerable angst and dissension within the colonial bureaucracy about how to manage the pressures coming from French and other European interests to open the southeastern periphery for resource extraction. This paper examines those debates in the context of residents’ lived experiences of colonial dispossession and partial incorporation into a centralizing, modern state, especially through erasure of their sovereignty over land and the sub-surface. I argue that resource frontiers evince an uneven and ambivalent relationship to political frontiers, as diverse state and corporate actors contest how to incorporate people, territories, and resources into polities and markets. These contestations highlight the importance of bureaucratic procedure and the often quiet work of the colonial administrative apparatus in creating resource frontiers. I further argue that we must attend to silences and erasures in the colonial fashioning of resource frontiers—especially around land tenure issues—to understand the relationship of those frontiers to the diverse forms of sovereignty that were consolidated but not completely eradicated in the formation of the modern, territorializing state.