Thirty-Three Orientals Declare Uruguay's Independence

Context

Following the collapse of Spanish colonial authority in South America, the territory known as the Banda Oriental, or Eastern Bank of the Uruguay River, became a contested frontier. José Gervasio Artigas had led earlier efforts to secure autonomy, but Portuguese forces from Brazil occupied the region in 1816–1817 and formally annexed it as the Cisplatina Province in 1821 after Brazil’s own independence from Portugal.

What Happened

Juan Antonio Lavalleja, a veteran of Artigas’s campaigns who had taken refuge in Buenos Aires, organized an expedition of Uruguayan exiles and sympathetic volunteers. On the night of April 18–19, 1825, the group crossed the Uruguay River and landed at La Agraciada near Colonia del Sacramento. Although the landing party numbered only thirty-three men at the outset—hence their later name—the force quickly attracted local recruits.

Fructuoso Rivera, another former Artigas lieutenant who had briefly served the Brazilian administration, brought additional fighters from the interior and joined Lavalleja by late April. The insurgents advanced inland, securing towns and calling a representative assembly that met in the town of Florida. On August 25, 1825, the assembly proclaimed the independence of the Oriental Province from the Empire of Brazil while declaring its incorporation into the United Provinces of the Río de la Plata.

Aftermath

The United Provinces formally recognized the province’s incorporation on October 24, 1825. Brazil responded by declaring war in December, initiating the Cisplatine War. Local assemblies ratified the Florida declaration, and a provisional government began to function under the protection of forces from Buenos Aires.

Legacy

The three-year conflict ended in 1828 with the Treaty of Montevideo, negotiated under British mediation, which established Uruguay as an independent buffer state between Argentina and Brazil. August 25 remains Uruguay’s national Independence Day, commemorating the moment when local patriots asserted sovereignty and reshaped the political geography of the Southern Cone.