This contribution details an early chapter in the long and complex history of the relationship of international socialism with anticolonial movements in British India. It tells a story of global intellectual interaction that informed and shaped international socialism as well as transnational anticolonialism between 1918 and 1924. It does so by highlighting a few aspects of this history. First, it discusses why radical anticolonialists gravitated towards international communism in the wake of the First World War. Second, it shows how the intersection between Marxist theory and anticolonial thought resulted in a capacious understanding of imperialism as a mode of capitalist production and organization of resources. Third, it illustrates how in interactions with radical anticolonialists from colonies like India, communists across the industrial world came to recognize national revolutionary movements as an integral part of the imminent world international revolution. Finally, it reveals the British colonial state’s anxiety about the rise of subversive ideas in the interwar years and its beleaguered response to this type of transnational anticolonialism.