republic · South America

United Provinces of the Río de la Plata

1810 CE – 1831 CE · capital Buenos Aires

The revolutionary state formed in Buenos Aires in 1810 that declared independence from Spain in 1816 and became the core of Argentina.

Origins

The May Revolution of 25 May 1810 replaced the viceroy of the Viceroyalty of the Río de la Plata with a Primera Junta in Buenos Aires. Armies were sent to spread the revolution, but Paraguay and Upper Peru resisted, and Montevideo held out for Spain until 1814.

Rule and society

Government passed from juntas to triumvirates and, from 1814, Supreme Directors. Manuel Belgrano created the blue and white flag in 1812, and the Assembly of the Year XIII abolished titles and freed children born to enslaved mothers. The Congress of Tucumán declared independence on 9 July 1816. José de San Martín's Army of the Andes liberated Chile in 1817 and 1818. Conflict between Buenos Aires and federalist provinces, such as those of the Federal League, was constant.

Decline and legacy

After the Battle of Cepeda in 1820 central government collapsed. Bernardino Rivadavia's presidency and a war with Brazil over Cisplatina followed. The Federal Pact of 1831 created the Argentine Confederation.

Lineage

Viceroyalty of the Río de la Plata 1776 CE – 1814 CERepublic of Entre Ríos 1820 CE – 1821 CEUnited Provinces of the Río de la PlataArgentine Confederation 1831 CE – 1861 CE

Connections (2)

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Cite this page
APA
The Epoch Institute. (2026). United Provinces of the Río de la Plata. In The Epoch Institute States Register. https://the-epoch-institute.org/state/united-provinces-of-the-rio-de-la-plata
MLA
“United Provinces of the Río de la Plata.” The Epoch Institute States Register, The Epoch Institute, 2026, https://the-epoch-institute.org/state/united-provinces-of-the-rio-de-la-plata. Accessed .
Chicago
The Epoch Institute. “United Provinces of the Río de la Plata.” The Epoch Institute States Register. 2026. https://the-epoch-institute.org/state/united-provinces-of-the-rio-de-la-plata.
Harvard
The Epoch Institute (2026) ‘United Provinces of the Río de la Plata’, The Epoch Institute States Register. Available at: https://the-epoch-institute.org/state/united-provinces-of-the-rio-de-la-plata (Accessed: ).

Last reviewed October 2026Random state ↻