In order to question the modernist common sense of mainstream sociology, epitomised today by the charge of methodological nationalism, this article offers an overall reading of Marcel Mauss’s The Nation. Conceived during the Great War and written mainly in 1920, Mauss’s work radically re-examined both the nation and nationalism from a regenerated sociological viewpoint centered on the relations between societies. Distinguishing between partial relations of exchange and total relations of encounter, Mauss came to discover the gift as a total social fact, seeing it as the traditional unconscious spring of the federative dynamics that had to be reactivated in Europe to associate its nations in a great ‘Inter-nation’ and avoid the risk of a new total war. The Nation, by reviving the original ambition of Émile Durkheim’s sociology to be a way rethinking and reshaping the concepts and institutions of modernity, helps us explore the contradictions and pathologies involved in the concept and history of the nation, in a situation currently marked by the return of nationalism and the quest for a social Europe.