This article examines the economic effects produced by the saltpeter development of Tarapaca at the end of the 19th century, based on the study of the transformation processes of agricultural production and the irrigation system in the Department of Cerrillos (Province of Salta-North of Argentina)). For this purpose, emphasis is placed not only on the characteristics of agricultural production at the end of the 19th century, but also on the economic transformations that led to the increase of the agrarian frontier, with the consequent manifestation of a series of conflicts over the distribution of land. irrigation water. In our investigation it is demonstrated that the demand of cattle by the nitrate region was the promoter of an economic reorientation produced in the Valleys of Lerma and Calchaqui, which began to develop according to livestock demand but, with significant effects on the agro and in the demand of water for irrigation. For this reason, the research acquires relevance given that it allows to understand that before the processes of "Atlantization" for the development of the agro-export market of the regional economies of northern Argentina, there were areas that were economically influenced by other regions, such as Tarapaca.
