Overview
The Viceroyalty of the Río de la Plata or Viceroyalty of the River Plate was the last to be organised and also the shortest-lived viceroyalty of the Spanish Empire in the Americas. It was established in 1776 from several former Viceroyalty of Peru dependencies that mainly extended over the Río de la Plata Basin, roughly the present-day territories of Argentina, northern Chile, Bolivia, Paraguay and Uruguay, extending inland from the Atlantic Coast. The colony of Spanish Guinea also depended administratively on the Viceroyalty of the Río de la Plata. Buenos Aires, located on the western shore of the Río de la Plata estuary flowing into the Atlantic Ocean, opposite the Portuguese outpost of Colonia del Sacramento, was chosen as the capital.
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