Provincias Unidas del Río de la Plata

United Provinces of the Río de la Plata (United Provinces of South America)
Provincias Unidas del Río de la Plata (Provincias Unidas de Sudamérica)
1810–1831
Flag of the United Provinces, 1818 Coat of arms
Anthem Patriotic March
United Provinces in 1816, during both the Independence War and the Civil War. In lighter blue, the territories not under Independentist control. In darker shades, the Supreme Directorship loyalist provinces, and the Federal League provinces.
Capital		Buenos Aires (1810-1820) (1826-1827)
Languages		Spanish
Religion		Christianity
Government		Republic
Historical era		Napoleonic Wars
•	British invasions of the Río de la Plata	1806-1807
•	May Revolution	25 May, 1810
•	Declaration of Independence	9 July 1816
•	Battle of Cepeda End of centralized authority	1 February 1820
•	First Presidency	8 February 1826
•	Treaty of Montevideo Independence of Uruguay	28 August 1828
•	Pacto Federal	4 January, 1831
Currency		Real (from 1813) Sol (from 1815) Peso fuerte (from 1826)
Preceded by Succeeded by Viceroyalty of the Río de la Plata Argentine Confederation Uruguay Bolivia Empire of Brazil

The United Provinces of the Río de la Plata (Spanish: Provincias Unidas del Río de la Plata), earlier known as the United Provinces of South America (Spanish: Provincias Unidas de Sudamérica), a union of provinces in the Río de la Plata region of South America, emerged from the May Revolution in 1810 and the Argentine War of Independence of 1810–1818. It comprised most of the former Viceroyalty of the Río de la Plata dependencies and had Buenos Aires as its capital.

It is best known in Spanish-language literature as Provincias Unidas del Río de la Plata ("United Provinces of the River of Silver"), this being the most common (occasionally the official) name in use for the country until the enactment of the 1826 Constitution. The Argentine National Anthem refers to the state as "the United Provinces of the South". The Constitution of Argentina recognises Provincias Unidas del Río de la Plata as one of the official names of the country, referred to as "Argentine Nation" (Nación Argentina) in modern legislation.

The United Provinces of South America were bordered on the south by the sparsely populated territories of the Pampas and Patagonia, home to the Mapuche, Ranquel and Puelche peoples. To the north, the Gran Chaco was populated by the Guaycuru nations. To the northwest, across the Upper Peru, lay the Spanish Viceroyalty of Perú. Across the Andes, to the west, was the Spanish-controlled Captaincy General of Chile. To the northeast was Colonial Brazil, a part of the Portuguese Empire (in 1815, the United Kingdom of Portugal, Brazil and the Algarves), later the Empire of Brazil in 1821.