This essay explores the way in which Italian colonialist imaginary perceived the French protectorate of Tunisia and the Italian migrants settled there. The first part of the paper deals with the relations between French capitals and Italian workforce within Tunisian colonial society. Then I analyse how the colonial regime and the nationalist narratives fostered communitarian fractures breaking the internationalist labor movement. Tunisian case reveales how the diasporas in colonial spaces during the age of high imperialism were interesting political and social laboratories of identities. The paper particularly focuses on how the Tunisian context was a place of peculiar Italian nation-building project based on colonial and racial categories. Italian colonialist imaginary not only included Tunisia in a Greater Italy, but also assessed the Sicilian settlers in French Tunisia as a colonial avant-garde for overseas expansions, especially to Libya. In the end I argue that this Tunisian case study could show us how tight is the link between nation-, race- and class-making processes.