Second Cevallos expedition

Spanish–Portuguese War (1776–1777)
Part of the Spanish–Portuguese wars
Date February 1776 to 24 February 1777 Location South America Result Spanish victory First Treaty of San Ildefonso
Belligerents
Spanish Empire	Portuguese Empire
Commanders and leaders
Pedro Antonio de Cevallos Juan José de Vértiz y Salcedo	Robert MacDouall Jorge Hardcastle
Strength
1,450 initially 9,000 expeditionary corps	6,000 initially

The Spanish-Portuguese War was fought between 1776 and 1777 over the border between Spanish South America and Portuguese South America.

In the previous Spanish-Portuguese War 1762–1763, Spain had conquered the Colonia del Sacramento, Santa Tecla, San Miguel, Santa Teresa and Rio Grande de São Pedro in the First Cevallos expedition.

Colonia del Sacramento was returned to Portugal in the Treaty of Paris, but Santa Tecla, San Miguel, Santa Teresa and Rio Grande de São Pedro remained in Spanish hands.

The Portuguese started assembling troops and harassing the Spanish in 1767. Over the years the Portuguese built up an army of 6,000 men, considerably more than the 1,450 Spanish troops in the area. The matter escalated in February 1776 when two Portuguese fleets under Robert MacDouall and Jorge Hardcastle landed troops near the fortress of Rio Grande de São Pedro, and started shelling the Spanish fort. A Spanish fleet under Francisco Javier Morales drove off the Portuguese fleet after a three-hour battle where the Spanish fleet suffered sixteen killed and 24 wounded, while the Portuguese lost two vessels.

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Wikipedia