United Provinces of the Río de la Plata

The United Provinces of the Río de la Plata was the name of the state that emerged in Buenos Aires after the May Revolution of 1810 and lasted, through wars and constant changes of government, until 1831. It claimed the lands of the former Spanish Viceroyalty of the Río de la Plata but never held them all, and it declared independence from Spain in 1816. The state is the direct forerunner of Argentina, whose constitution still lists its name among the country's official titles.

The crisis began in Spain. When Napoleon captured King Ferdinand VII and French forces broke up the Spanish resistance government that had appointed the viceroy, many in Buenos Aires judged that his authority had lapsed. On 25 May 1810 an open town council removed Viceroy Baltasar Hidalgo de Cisneros and set up the Primera Junta. Its members swore loyalty to the captive king and did not declare independence, though historians still argue over whether this was a tactic or a genuine aim. American-born criollos, shut out of high office under Spanish rule, led the movement.

The new government sent circulars and armies to the provinces, with mixed results. Paraguay repelled an expedition and went its own way. Upper Peru, today's Bolivia, was held by royalist forces of the Viceroyalty of Peru, and repeated campaigns from Buenos Aires failed to hold it. Montevideo stayed loyal to Spain until it surrendered in 1814, after which José Gervasio Artigas made the Eastern Bank, today's Uruguay, the centre of a federal league of provinces opposed to rule from Buenos Aires. Power in the capital itself passed from juntas to two triumvirates and, from 1814, to a Supreme Director.

A congress meeting at Tucumán elected Juan Martín de Pueyrredón Supreme Director and on 9 July 1816 declared independence from Ferdinand VII and his successors, issuing the text in Spanish, Quechua and Aymara. The decisive military effort was led by José de San Martín, who spent two years building an army in Cuyo and in January 1817 led it across the Andes to attack the royalists in Chile, part of the wider Spanish American wars of independence. Meanwhile Portuguese-Brazilian troops invaded the Eastern Bank from 1816 and took Montevideo in 1817, which the Buenos Aires government did little to resist.

Conflict between centralists in Buenos Aires and federalists in the provinces had already turned violent in 1814. A centralist constitution adopted in 1819 was rejected by much of the country, and the Army of the North then mutinied rather than fight in the civil war. On 1 February 1820 the federal leaders of Santa Fe and Entre Ríos defeated the Directory's forces at Cepeda, and the national government was dissolved soon afterwards, leaving the provinces to govern themselves.

A national government was briefly revived when Bernardino Rivadavia served as president from 8 February 1826 to 27 June 1827. Its main burden was a war with the Empire of Brazil over the Eastern Bank, fought from December 1825 to August 1828 and ended by a preliminary peace under which both sides gave up their claims and Uruguay became independent. Civil war then resumed, and on 4 January 1831 Buenos Aires, Entre Ríos and Santa Fe signed the Federal Pact, a federal alliance that opened the era of the Argentine Confederation.

Our 1815 map shows the United Provinces between Paraguay and the Viceroyalty of Peru to the north and Portuguese Brazil to the east, with the Pampas and Patagonian peoples to the south.