The
Uruguayan War (10 August 1864 – 20 February 1865) was fought between
Uruguay's governing
Blanco Party and an alliance consisting of the
Empire of Brazil and the Uruguayan
Colorado Party, covertly supported by
Argentina. Since its independence, Uruguay had been ravaged by intermittent struggles between the Colorado and Blanco factions, each attempting to seize and maintain power in turn. The Colorado leader
Venancio Flores launched the Liberating Crusade in 1863, an insurrection aimed at toppling
Bernardo Berro, who presided over a Colorado–Blanco coalition (Fusionist) government. Flores was aided by Argentina, whose president
Bartolomé Mitre provided him with supplies, Argentine volunteers and river transport for troops.