This paper deals with the transnationalism of racial anthropological frameworks and its role in the understanding of human difference during India’s decolonization and nation-building. With attention to the circulation of scientific objects, I focus on the practices and articulations of Irawati Karve (1905–1970), an Indian anthropologist with a transnational scientific trajectory and nationalistic political engagements. I argue that Karve’s adaptation of an internationally validated German racial approach to study caste, ethnic and religious groups contributed to the further racialization of these categories as well as to the racialization of nationalistic projects in Maharashtra and India. I conclude with a reflection on the transnationalization of the coloniality of racialization.