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Definition: Triple Alliance, War of the from Chambers Dictionary of World History

A devastating war, fought by Paraguay against the combined forces of Brazil, Argentina and Uruguay (the Triple Alliance), which was provoked by the ambitions of the Paraguayan dictator, Francisco Solano López. The eventual victory of the Allies (most of the troops were provided by Brazil) was achieved at the cost of reducing the male population of Paraguay by nine-tenths.

Summary Article: Paraguayan War (1864–1870)
from The Encyclopedia of War

The Paraguayan War (also known as the the War of the Triple Alliance) was the largest and most costly conflict in the postindependence history of South America. The war pitted the highly regimented society of Paraguay against the combined forces of Argentina, Brazil, and Uruguay. The origins of the conflict are rooted in unresolved border questions, interference by Argentina, Brazil, and Paraguay in the internal affairs of Uruguay, and the personal ambitions of Paraguay's dictator, Francisco Solano López. The war would have disastrous consequences for Paraguay, resulting in the loss of almost 80 percent of its male population, large-scale destruction of its infrastructure, and the ceding of land to both Argentina and Brazil.

Uruguay became an independent nation in 1828 as a result of the war between Argentina and Brazil. Immediately upon its inception, two parties began to form around rival leaders. By 1836 these rival groups coalesced into the Blanco (White) and Colorado (Red) factions, ushering in an era of sustained instability. Relations between the two factions were contentious. Whichever side was not holding power would intrigue against its rivals, usually by involving either Argentina or Brazil.

In 1863 a civil war broke out between the two factions as the ruling Blancos were attacked by the Colorados. The Brazilians supported the Colorados, while the Blanco faction had allied with Paraguay and its leader, López. Instead of directly supporting his Blanco allies López attacked the Brazilian province of Matto Grosso on his northern border. The attack was successful but did little to stop a Colorado victory. Enraged by López's attack, the Brazilians declared war in March 1865.

López wanted to obtain the Brazilian province of Rio Grande do Sul, but an invasion required passage through Argentina. On April 13, 1864 he attacked the Argentine river port of Corrientes in anticipation of an invasion from Brazil. López had hoped that the local caudillo, General Justo Jóse de Urquiza, a Blanco sympathizer and an opponent of Argentine President Bartolomé Mitre, would support him, or at the very least remain neutral. Instead, Urquiza remained loyal to Argentina. On May 1, 1865, representatives from the governments of Argentina, Brazil, and Uruguay signed a pact forming the Triple Alliance against Paraguay.

The disposition of the Paraguayan forces seemingly placed them at a disadvantage. They had only a fraction of the men available to either Brazil or Argentina. López had about forty thousand troops, although only about a fourth of them were regulars. He could also count on only thirty thousand reserves from the remaining male population. Paraguay had a small river navy to defend the Paraguay and Parana‘ river borders and provide logistical support for his troops. López had the industrial capacity to provide some of his war needs, but his key advantage lay in his absolute control of the Paraguayan nation and the faithful loyalty of his Spanish/Guarani mestizo troops.

The Allies had a considerable manpower advantage. Brazil's regular forces numbered close to 34,000 men, while Brazilian population reserves provided another fifty thousand troops by 1866. Brazil also possessed a regular navy which would allow it to blockade the Parana‘ River and deny Paraguay access to material from the outside. The Argentine military forces numbered about eighteen thousand, but internal pressures would keep them from committing their entire force to the war. Uruguay, for its part, provided only a small force of 1,500 veteran troops.

Both sides had anticipated a quick resolution and had been poorly prepared for the five year conflict that followed. The Allies were unable to mount a coordinated offensive until the summer of 1865. There was no unified command for the war, as primacy of command depended upon the location of the theater of battle. For his part, López lacked the strategic skill necessary for a David vs. Goliath fight. He had squandered his opportunity to capitalize on the Uruguayan Civil War to secure a useful ally. He also failed to secure the support or neutrality of Urquiza, leaving him with enemies on almost every front.

Using Brazilian riverboats, Argentine forces temporarily recaptured Corrientes on May 25, 1865. Although Paraguay immediately recaptured Corrientes, López realized that he needed to destroy the Allies’ river naval capacity to keep his troops from being flanked and his lines of communications from being severed. On June 11, 1865 López mounted a surprise attack on the Brazilian river squadron's base at Riachuelo. Using a combined force of armed river steamers and land-based field pieces, the artillery duel lasted for several hours until the Brazilian flagship Amazonas rammed and disabled four of the enemy ships, forcing Paraguayan forces to retreat. Although in terms of men and material the defeat was not catastrophic to López, his inability to dislodge the Brazilian fleet from the Parana‘ River would prove decisive in the long-term conduct of the war. Once the Allies gained full mastery of the river ways, Paraguay would be forced into a defensive war.

Concurrently, López dispatched a second invasion force toward Rio Grande de Sul. The Paraguayan force split into two parts, the smaller part staying west of the Uruguay River and marching through Argentine territory, while the greater force was concentrated east of the river, on Brazilian soil. Their objective was twofold. First, López intended to rally Argentine and Uruguayan Blanco sympathizers to his side by making a push toward Uruguay. Second, López wanted to secure the Uruguay River so that he could gain a strategic advantage when he invaded Rio Grande de Sul.

The offensive was thwarted by the efforts of Uruguayan President Venancio Flores. The leader of the Colorados led an Allied attack against the smaller of the two Paraguayan forces, beating them at Yatai and cutting off the larger force from their line of retreat. The Paraguayan commander, fearful of retreating without orders, occupied the Brazilian town of Uruguayana, which was quickly surrounded by the Allies and besieged. Cognizant of their hopeless situation, the remnants of the Paraguayan invasion force surrendered on September 18, 1865. The Paraguayan offensive had been a disaster for López; he lost over twenty thousand soldiers and failed to attract dissident Argentine and Uruguayan elements to his side.

After the failure of his offensive, López withdrew his forces toward the fortress of Humaitá, located 130 miles south of Asunción upon the Paraguay River. López understood that the difficult topography of southern Paraguay, and the paucity of potential supply routes for the Allies, compelled them to attack up the river. He set up a series of defensive works and gun batteries radiating south from Humaitá all the way to the strong point of Paso de Patria at the confluence of the Paraguay and Paraná rivers. Meanwhile, the Allies temporized for many months, fending off Paraguayan raiding parties and an occasional artillery duel. The Allies’ offensive began in earnest in April 1866 with an attack on Fort Itapuru.The Paraguayans were forced to abandon their positions, but they fell back in good order. López mounted a surprise counterattack on May 2 through the swamp of Estero Bellaco, destroying the Allies’ forward elements but incurring heavy casualties.

The Arrival of the Allied Army at Itapiru, Paraguay, 1866, by Cándido López (1840–1902). Museo Historico Nacional, Buenos Aires, Argentina/Index/Bridgeman Art Library.

On May 22 the Allies continued their offensive toward the next line of Paraguayan defenses. López preempted their movements by committing the bulk of his best troops (about twenty thousand men) to simultaneous attacks upon the Allied flanks at Tuyuti. His objective was to shatter the wings of the Allied army and encircle the center, pinning them against the Paraguayan fortifications to the north. In spite of the fanatical courage of the Paraguayans, López lost half of his troops, further underscoring the fatal deterioration of available manpower. The Paraguayans withdrew to their system of fortifications dubbed the Rojas Lines, which the allies assaulted on three occasions between July 11 and July 18. This time the Allies took heavier casualties than López and desisted from any more major assaults until the arrival of reinforcements.

In August 1866 the Allies decided to use their naval supremacy to effect a landing behind the Paraguayan trenches at Curupaiti and force them to abandon the Rojas Lines. The landing was successful and on September 1 the allies captured the gun battery at Curuzu, opening the way toward Curupaiti. In an effort to salvage a deteriorating situation López held a peace armistice with Mitre. The Allies were unwilling to accept peace without López's resignation, a condition that was unacceptable to the dictator.

After the failure of the armistice, the allies continued their push toward Curupatai. On September 22 they mounted a frontal attack with twenty thousand men. The inability of the naval artillery to effectively support their attack led to heavy casualties and the suspension of the operation. By the end of 1866, Mitre and Flores were forced to return to their respective countries to deal with unrest and the Brazilians brought in the duke of Caixas as the Allied commander. Major operations recommenced in July 1867. The Allied troops cut through the swamps east of the Rojas Line, flanking the Paraguayan just north of their headquarters, and forcing López to pull his defensive front closer to Humaitá.

On November 2, López dispatched a force of nine thousand troops who managed to surprise the Allies at Tuyuti. The attack could have resulted in a rout, except that the hungry Paraguayan troops were under orders to plunder the enemy camp. The Allied troops regrouped and counterattacked, inflicting terrible losses on the Paraguayans. Hemmed in at Humaitá, López waited for the Allied river attack.

On February 19, 1868, six armored Brazilian ships ran the gauntlet and successfully pierced the Paraguayan defenses. These ships proceeded to shell Asunción, prompting López to order the abandonment of the Paraguayan capital. Simultaneously, Allied troops chipped away at the defenses north and east of Humaitá, narrowing the escape routes for the Paraguayan army. By July, López abandoned his lines, leaving only 1,800 men behind. The remaining Paraguayan troops crossed the Paraguay River and marched north along the west bank toward friendly territory. On August 5 the remnants of the Humaitá defenders surrendered.

López refused to accept defeat. He blamed the mounting defeats on the cowardice or perceived treasonous behavior of his subordinates and political enemies. His increasing paranoia led to the imprisonment and execution of many of his own citizens, further weakening his shattered nation. López's excesses were permitted by the fanatical loyalty of the Paraguayan people. He intended to fight until the bitter end and his people proceeded to commit suicide along with their leader.

By late 1868 the duke of Caixas concentrated his forces to dislodge López from his new position near Asunción. A series of battles fought around the towns of Villeta and Angostura broke the back of the remaining Paraguayan forces. The Allies captured Asunción on January 1, 1869, but López managed to escape. Convinced of their victory the Allies slowed their offensive, permitting López the opportunity to rebuild a force from the shattered remnants of his people. This force was limited by a lack of supplies and once the Allies resumed their offensive they were overmatched. On March 1, 1870 the Allies caught up to López at Cerro Cora, killing the dictator and massacring the remnants of his army. Peace was signed with the Allies on June 20, 1870. After the war, Argentina and Brazil proceeded to carve away portions of Paraguay and colonize its decimated population. The tremendous losses in population meant that Paraguay's future would be dictated by the whims of its more powerful neighbors for more than a generation.

SEE ALSO: Blockades; Chaco War (1932–1935); Ethnic cleansing; Total war.

Further Reading
  • Kohn, R. (2008) Weep, Grey Bird, Weep: The Paraguayan War, 1864-1870. Author House Bloomington.
  • Kray, H. Whigham, T. (Eds.) (2004) I Die with My Country: Perspectives on the Paraguayan War, 1864-1870. University of Nebraska Press Lincoln.
  • Leuchars, C. (2002) To the Bitter End: Paraguay and the War of the Triple Alliance. Greenwood Press Westport.
  • Saeger, J. S. (2007) Francisco Solano López and the Ruination of Paraguay. Rowman and Littlefield Plymouth.
  • José María Herrera
    Wiley ©2012

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