History of Paraguay (to 1811) Buenos Aires in 1580, the steady deterioration in the importance of Asunción contributed to growing political instability within the province. In 1617 the Río de la Plata Province was divided into two smaller provinces: Paraguay, with Asunción as its capital, and Río de la Plata, with headquarters in Buenos Aires. With this action, Asunción lost control of the Río de la Plata estuary and became dependent on Buenos Aires for maritime shipping. In 1776 the crown created the Viceroyalty of Río de la Plata; Paraguay, which had been subordinate to Lima, now became an outpost of Buenos Aires. Located at
San Pedro Department, Paraguay San Pedro Department, Paraguay San Pedro () is a department of Paraguay. The capital is the city of San Pedro de Ycuamandiyú. During the 17th and 18th centuries there was even greater political and population instability than in Concepción. The Mbayá and Payagua native tribes threatened all the area between the Ypané (in the north) and Manduvirá (in the south) Rivers and the valley by the Jejuí River. In 1660 the natives revolted in Arecajá against the postal parcel system, causing the disappearance of this town. To help regenerate this area, the Missions San Estanislao (1749), Villa del Rosario (1786)