The aim of this paper is, in celebration of the life of Dr. Enrique M. Barba, try to detect the imprint of their work, and his way to work in my work and that of colleagues with whom I work at the Instituto de Historia Argentina, Facultad de Humanidades, UNLP. Enrique Mariano Barba not dedicate first to the colonial history, and then, to the Rosas' federalism. Always did 'history of Argentina'. By bringing together in a single glance their most representative works reveals that the problem that interested him, from his doctoral thesis, was the formation of nation-state.