This paper examines how two Caribbean islands, Puerto Rico and Jamaica, developed ideas of national identity while negotiating political emancipation within two distinct, yet allied Anglophone empires. We can see this process through the Olympic movement and referred to here as “colonial Olympism.” Both Puerto Rico and Jamaica participated as colonies of the United States and Great Britain at international sporting events from 1930 to the 1950s. More than a benevolent gesture by the U.S. or Great Britain, Puerto Rico and Jamaica’s participation was intended to foster international goodwill through sport, including crucial notions of Pan-Americanism. Comparing these two islands, and the metropolises they represented, offers a good way to understand the commonalities and differences in U.S. and Great Britain’s geopolitical interests in Latin America. However, the Olympic and the Pan-American Games, gave both colonies the perfect scenario to perform as separate nations and fed a sense of distinct peoplehood. Sport leaders from both islands negotiated their way into nationhood by the very fact of participating in the Olympic movement, albeit as non-sovereign states. In turn, having Olympic nationhood became another important tool in both islands’ quest for decolonization, contributing an important angle to better understand twentieth-century international politics and decolonization processes.