A New Key Port in America: The Fortification of Buenos Aires in the Seventeenth Century

The outcome of the 1640 Portuguese rebellion against Spanish rule instantly turned Buenos Aires into a new key port in Spanish America, given its location on the frontier with now-Portuguese Brazil. Consequently, the Spanish imperial bureaucracy focused on its fortification in the second half of the century. That case was part of a larger process during that century of fortifying Spanish American cities with walls and more complex elements. The present article will focus on the role of the local authorities and their response to the crown’s plan, illuminating the difficulties and mistakes in that ultimately unsuccessful effort, such as hiring a lack of skilled workers, especially engineers, and the misconceiving of the territory and its resources. For that purpose, the research will be based on unpublished documents from the Archivo Histórico Nacional and Archivo General de Indias, as well as various plans for the projects.