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
Geography of Paraguay Paraná; the mountain chain has an average height of . Separated from the Eastern region by the Paraguay River, the Chaco region is a vast plain with elevations reaching no higher than and averaging . Covering more than 60 percent of Paraguay's total land area, the Chaco plain slopes gently eastward to the Río Paraguay. The Paraguayan Chaco is subdivided into two parts. The "Alto Chaco" (Upper Chaco), also called "Chaco Seco" (Dry Chaco) is the western three-quarters of the region, bordering on Bolivia, while the "Bajo Chaco" (Lower Chaco) or "Chaco Húmedo" (Humid Chaco) borders on the Paraguay River.