This paper analyzes how cultural diversity in Argentina is calling into question modern political concepts like republic, nation or democracy. The phenomenon of population movements, the demand for recognition of indigenous people's rights, or the conflicts arising from claims to regions' right to life and identity - as in the case of the town of Gualeguaychú in Argentina - challenge the logic of the nation-state and its sovereignty as well as the republican principles of liberty, equality and fraternity. The author examines how far the representation of the Argentinean republic at the time of its foundation included a standardizing vision of diversity, and how the legacy of this representation brought about an ambivalence between a universalist wish to take part in the progress of humanity and the reality of an exclusive democracy that valued one culture over others. It studies the narrative of national identity and attempts to describe how, proceeding from this narrative, the opposition between civilization and barbarity affects the way Latin Americans see the great challenges presented by the future of democracy, and by the recognition of the plurality of cultural allegiances.