Key Facts
- Expeditionary force size
- 2,700 soldiers
- Siege start date
- 1 October 1762
- Capitulation date
- 3 November 1762
- Treaty ending campaign
- Treaty of Paris, 1763
- Forts captured (Jan–Apr 1763)
- Santa Tereza, San Miguel; village of Rio Grande
Strategic Narrative Overview
Cevallos sailed from Buenos Aires on 3 September 1762 with 2,700 troops, arriving near Colónia do Sacramento on 7 September and opening a formal siege on 1 October. The settlement capitulated on 3 November. A subsequent joint Anglo-Portuguese counterattack by sea was repulsed after a British warship was destroyed. From January to April 1763, Cevallos seized the forts of Santa Tereza and San Miguel and occupied the village of Rio Grande.
01 / The Origins
In 1762, Spain entered the Seven Years' War alongside France under the Family Compact, partly driven by French diplomatic pressure. Targeting Portugal as France's ally Britain's partner, Governor of Buenos Aires Pedro Antonio de Cevallos was notified months in advance of Spain's intent to declare war on Portugal, giving him time to organize an offensive against the Portuguese settlement of Colónia do Sacramento on the Río de la Plata.
03 / The Outcome
Learning of the 1763 Treaty of Paris while at Rio Grande, Cevallos ended his campaign. Under the treaty, Colónia do Sacramento was returned to Portugal, though other outposts remained under Spanish control. Portugal's refusal to accept these losses fuelled ongoing border incursions and ultimately led to an undeclared war in 1776–1777, during which Cevallos again took Colónia do Sacramento, this time permanently under the First Treaty of San Ildefonso.
Belligerents & Mobilization Analysis
Side A
1 belligerent
Pedro Antonio de Cevallos.
Side B
2 belligerents
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.