HistoryData
Historical ConflictCorrientes Province

Corrientes Campaign

Paraguay's invasion of Argentina's Corrientes Province triggered the Treaty of the Triple Alliance, uniting Argentina, Brazil, and Uruguay against Paraguay.

Duration & Scope

1865 1866

1 year

Key Facts

Campaign phase
Second campaign of the Paraguayan War
Duration
1865–1866
Treaty signed
Treaty of the Triple Alliance
Concurrent operation
Siege of Uruguaiana
Outcome
Paraguayan invasion repelled

Strategic Narrative Overview

Paraguayan forces seized the city of Corrientes and advanced through the province, opening a southern front in what became a multi-theatre conflict. The campaign unfolded concurrently with the Siege of Uruguaiana, stretching Paraguayan operational capacity. The allied nations — Argentina, Brazil, and Uruguay — mobilised to counter the invasion, progressively pushing Paraguayan forces back and consolidating a unified military response under the framework of the Triple Alliance.

01 / The Origins

Paraguay, already at war with the Empire of Brazil, escalated the conflict by invading Argentina's Corrientes Province in 1865. President Francisco Solano López ordered Paraguayan forces across the border, occupying the city of Corrientes and several other towns. This aggressive expansion into Argentine territory forced Argentina and Uruguay to align with Brazil, culminating in the signing of the Treaty of the Triple Alliance and a formal declaration of war against Paraguay.

03 / The Outcome

The Paraguayan invasion of Corrientes ultimately failed, with allied forces repelling the occupation and securing Argentine territory. The campaign's failure marked a strategic turning point: rather than knocking Argentina out of the conflict, Paraguay's aggression solidified the Triple Alliance coalition. This set the stage for the subsequent allied invasion of Paraguay itself in later campaigns of the broader Paraguayan War.

Belligerents & Mobilization Analysis

Side A

1 belligerent

Paraguay

Side B

3 belligerents

ArgentinaEmpire of BrazilUruguay
Outcome
Paraguayan invasion repelled; Argentina and Uruguay joined Brazil in declaring war on Paraguay under the Treaty of the Triple Alliance.

Location

Map of Corrientes, ArgentinaMap of Corrientes, ArgentinaCorrientes, Argentina