Uruguay: Independence Movement

Uruguay's independence movement grew out of the broader wars against Spanish colonial rule that swept South America in the early nineteenth century. José Gervasio Artigas led an early revolutionary campaign beginning in 1811 to expel Spanish authority from the Banda Oriental, the territory that would become Uruguay, and to resist domination by Buenos Aires. Spanish rule collapsed, but the territory was subsequently annexed by the Portuguese-Brazilian Empire in 1821 as the Cisplatine Province, extending foreign control over the region for several more years.

In April 1825, a band of exiles known as the Thirty-Three Orientals, led by Juan Antonio Lavalleja and reinforced by troops from Buenos Aires, crossed the Río de la Plata and launched an insurrection that quickly gained control of the countryside. On 25 August 1825, a congress convened at Florida issued a formal Declaration of Independence from Brazil and voted to join the United Provinces of the Río de la Plata, a move that triggered the Cisplatine War between Argentina and Brazil over control of the territory.

By 1828, the war had reached a stalemate, and British diplomats, eager to secure a neutral buffer state for their regional trade interests, brokered a settlement. The resulting Treaty of Montevideo, signed in August 1828, required both Argentina and Brazil to renounce their claims, formally establishing Uruguay as an independent nation.