In the decade of 1870’s, the Argentine Government had not yet consolidated their jurisdiction over the territorial extension corresponding to the former Viceroyalty of Río de la Plata. Besides being object of border disputes with other republics, regions of chaquenha, pampas and Patagonia remained under the effective domain of different indigenous groups. Identified to the idea of desert, these areas were prime targets for projects of integration to the world of civilization and modernity. This dissertation aims to analyze the proposed policies and military strategies drawn up by the Ministers of War and Navy Adolfo Alsina and Julio Argentino Roca, which were discussed in the Argentine National Congress in the 1870’s concerning the southern region and territorial confrontation of the Indian problem. This study seeks to interpret the conflicting positions of Alsina and Roca as complementary steps of nation-building process in Argentina and its corresponding territory. In this context, the delimitation of the national territory through the state occupation would enable the monopoly of power over the whole population who inhabited there, and the legal legitimacy of the application of that power, by disassociating Argentina from the image of the desert and the savagery of native populations as well as identifying it as the set of civilized nations.