The Paraguayan War, also known as the War of the Triple Alliance and the Great War in Paraguay, was a South American war fought from 1864 to 1870 between Paraguay and the Triple Alliance of Argentina, the Empire of Brazil, and Uruguay. With an estimated 400,000 deaths, the war was the deadliest and bloodiest in Latin America's history. It particularly devastated Paraguay, which suffered catastrophic losses in population – almost 70% of its adult male population died, according to some ...