This article traces the history of one geographical concept, hinterland, through changing political contexts from the 1880s through the 1970s. Hinterland proved a valuable tool for states attempting to challenge the global territorial order in both the Scramble for Africa and the postwar world of nation-states. In the context of German territorial demands in East Africa, colonial propagandists used hinterland to knit together the first longue-durée histories of the Indian Ocean to cast Zanzibar as a failed colonial power and win control of the coast. In the 1940s, Indian nationalists revived hinterland as a concept for writing about the Indian Ocean, utilizing the concept to link areas far from the ocean to an informal Indian empire that could be rebuilt to its premodern glory through naval expansion. In both contexts, hinterland provided a geographical framework to challenge British dominance on the Indian Ocean. The shifting meaning and usage of the term indicates continuities in territoriality between the Scramble for Africa and postwar internationalism.