THE WORLD ATLAS

War · 12 November 1864 – 1 March 1870

Paraguayan War (War of the Triple Alliance)

In 1864 Brazil intervened in a civil war in Uruguay against the Blanco government, an ally of Paraguay. Paraguay's president, Francisco Solano López, who had warned that he would treat an occupation of Uruguay as a threat, seized a Brazilian steamer in November and invaded Brazil's province of Mato Grosso.

When Argentina refused his army passage, Paraguay attacked Corrientes in April 1865, and Brazil, Argentina and Uruguay, now under a pro-Brazilian government, signed the Treaty of the Triple Alliance. Brazil's victory at Riachuelo gave the allies the rivers, and Paraguay's invading armies were destroyed or surrendered by late 1865. The allies invaded Paraguay in 1866, won at Tuyutí but were bloodily repulsed at Curupayty; under the Marquess of Caxias they took the fortress of Humaitá in 1868 and Asunción in January 1869. López fought on as a guerrilla until Brazilian troops killed him at Cerro Corá on 1 March 1870. Paraguay lost territory and a large share of its people.

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Dates
12 November 1864 – 1 March 1870
Casualties
Estimates vary widely, from about 150,000 to 500,000 deaths in all; Paraguay may have lost 60–70 percent of its population of about 420,000–450,000, by one estimate, while Brazil lost an estimated 50,000 soldiers and Argentina about 18,000, many of them to disease and hunger.

The sides

Triple Alliance (Brazil, Argentina, Uruguay)

Paraguay

Timeline of the Paraguayan War (War of the Triple Alliance)

  1. Brazilian troops invade Uruguay

    Brazil backed the Colorado rebel Venancio Flores against Uruguay's Blanco government of Atanasio Aguirre, which had rejected Brazilian demands over border raids. Paraguay's president, Francisco Solano López, warned in August that he would regard any occupation of Uruguay as an attack on the balance of the Platine region. Brazil ignored him, and on 12 October 1864 Brazilian troops crossed into Uruguay.

  2. Paraguay seizes the Brazilian steamer Marquês de Olinda

    The Brazilian steamer Marquês de Olinda, carrying the new governor of Mato Grosso up the Paraguay River, called at Asunción on 11 November 1864. López sent the warship Tacuarí after her; on 12 November she was stopped near Concepción and brought back, and all aboard were arrested. The same day Paraguay broke off diplomatic relations with Brazil. A month later López launched his first offensive.

  3. Paraguay invades Mato Grosso and attacks Fort Coimbra

    Two Paraguayan columns invaded the Brazilian province of Mato Grosso. One, carried up the Paraguay River, attacked Fort Coimbra on 27 December 1864; its garrison of 154 men held out for three days before slipping away upriver. Albuquerque and Corumbá fell in January 1865, and the overland column took Dourados, Miranda and Nioaque, and Coxim in April, but the Paraguayans did not push on to Cuiabá.

  4. The Uruguayan War ends with Flores in power

    After a Brazilian and Colorado siege, the Blanco stronghold of Paysandú fell on 2 January 1865, and the allies closed in on Montevideo. On 20 February 1865 the Blanco government gave way and Venancio Flores took power. Paraguay had lost its ally in Uruguay before its own army could arrive, and Flores's Uruguay sided with Brazil. Montevideo had been left isolated before it gave in.

  5. Paraguay's Congress votes for war with Argentina

    In January 1865 López asked Argentina to let 20,000 Paraguayan soldiers cross the province of Corrientes to strike at Brazil; President Bartolomé Mitre refused. A Paraguayan congress met in March and on 23 March voted for war with Argentina, accusing it of favouring Brazil, and made López a field marshal. The declaration was sent to Buenos Aires on 29 March.

  6. Paraguayan forces seize Corrientes

    On 13 April 1865 a Paraguayan squadron sailed down the Paraná, attacked two Argentine warships at Corrientes, and troops under General Wenceslao Robles took the city. Robles then advanced south along the river, taking Bella Vista, Empedrado and Goya, while the provincial government withdrew inland and Corrientes militia fought a guerrilla war. The attack brought Argentina into the war. Argentina declared war in early May.

  7. Brazil, Argentina and Uruguay sign the Treaty of the Triple Alliance

    On 1 May 1865 Brazil, Argentina and Flores's Uruguay signed a secret treaty in Buenos Aires, naming Argentina's president Bartolomé Mitre allied commander-in-chief. They pledged to fight until López was removed and laid down Paraguay's future borders in their own favour. The treaty was meant to stay secret, but Britain obtained a copy and published it in 1866. Uruguay's Flores commanded his own small army.

  8. Battle of Riachuelo: Brazil destroys Paraguay's navy

    On 11 June 1865 a Paraguayan squadron attacked the Brazilian fleet of Admiral Francisco Manoel Barroso on the Paraná below Corrientes. Barroso rammed and sank or wrecked most of the Paraguayan ships. The battle gave the allies control of the rivers up to Paraguay's border, cut the invading armies' supply lines and, for practical purposes, decided the outcome of the war.

  9. A Paraguayan army invades Rio Grande do Sul

    In May 1865 some 12,000 Paraguayans under Colonel Antonio de la Cruz Estigarribia crossed into Argentine territory south of Encarnación and marched down the Uruguay River. Estigarribia took the Brazilian town of São Borja on 12 June and then Itaqui, while a smaller column under Major Pedro Duarte advanced down the Argentine bank of the river. Brazilian commanders in the province could offer little resistance at first.

  10. Battle of Yatay

    Duarte's column, about 3,200 strong, had occupied Paso de los Libres on the Argentine bank opposite Uruguaiana, which Estigarribia entered on 5 August without supporting him. On 17 August 1865 an allied army under Venancio Flores attacked Duarte's position by the Yatay stream and destroyed his column; most of its men were killed or taken prisoner. Estigarribia, across the river, did not intervene.

  11. Estigarribia surrenders at Uruguaiana

    Besieged in Uruguaiana by Brazilian, Argentine and Uruguayan forces, with Emperor Pedro II, Mitre and Flores present, Estigarribia's starving garrison surrendered on 18 September 1865, against López's orders, and some 5,500 men became prisoners. López then pulled his armies out of Argentina and Brazil, and the war moved to Paraguay's own borders. Some of the prisoners were sold into slavery by Brazilian officers.

  12. The Paraguayan army completes its withdrawal from Corrientes

    On 3 October López ordered the southern army to leave Argentine territory. It evacuated the city of Corrientes on 22 October, looting the river towns as it went, and by 3 November 1865 some 27,000 men had recrossed the Paraná at Paso de la Patria with about 100,000 head of cattle. Corrientes's provincial government returned to its capital the same day.

  13. The allies cross the Paraná and invade Paraguay

    After months of gathering in camps north of Corrientes, the allied armies crossed the Paraná into Paraguay on 16 April 1866. General Manuel Luís Osório led the landing and beat back Paraguayan counterattacks around the fort of Itapirú. The allies pushed inland towards the swamps and trenches guarding the fortress of Humaitá, and were checked at Estero Bellaco on 2 May.

  14. Battle of Tuyutí, the largest battle of the war

    Hoping to destroy the allied army in one blow, López attacked its camp at Tuyutí on 24 May 1866 with about 23,000–25,000 men against some 32,000–35,000 allies. The attack nearly succeeded but was broken by allied resistance and Brazilian artillery. Paraguay lost about 12,000–13,000 killed and wounded, losses it could not replace, while the allies suffered some 4,000–6,000 casualties. Both armies then dug in for months.

  15. Battle of Curupayty: a bloody allied defeat

    After taking the fort of Curuzú on 3 September 1866 and a failed peace meeting between López and Mitre, the allies made a frontal assault on the Paraguayan trenches at Curupayty on 22 September, supported by Brazilian warships. General José E. Díaz's defenders held, and the allies lost between about 4,000 and 8,000 men, against at most a few hundred Paraguayans. Allied offensives stopped for ten months.

  16. Caxias begins the march around Humaitá

    The Marquess of Caxias, Brazil's commander from late 1866, rebuilt the disease-ridden allied army and on 22 July 1867 began a wide flanking march east and north around the fortress of Humaitá. On 2 November Brazilian troops took Tayí on the Paraguay River north of the fortress, cutting its land link with Asunción; López's counterattack at the second battle of Tuyutí the next day failed.

  17. Brazilian ironclads force the passage of Humaitá

    Humaitá's river batteries and a chain across the Paraguay River had blocked the allied fleet for two years. On 19 February 1868 Brazilian ironclads ran past the batteries under heavy fire, giving the allies control of the river and threatening Asunción. In early March López left the fortress with most of its garrison, crossing to the Chaco shore and moving north.

  18. The fortress of Humaitá falls

    The remaining garrison of Humaitá, starving after a long siege, beat off an allied assault on 16 July 1868. On the night of 24–25 July Colonel Francisco Martínez led the last defenders out across the river, and on 26 July the allies occupied the empty fortress. Trapped on the Chaco shore, about 1,300 survivors surrendered on 5 August. Humaitá had blocked the allied advance for more than two years.

  19. Ytororó and Avay: Caxias attacks the Paraguayans from behind

    López had fortified a line on the Pikysyry stream south of Asunción. Caxias built a road through the Chaco swamps, carried his army round the line and recrossed the river at Villeta. Turning south to attack from the rear, the Brazilians forced the bridge at Ytororó on 6 December 1868 at heavy cost, and on 11 December destroyed a Paraguayan division at Avay.

  20. Battle of Lomas Valentinas

    From 21 to 27 December 1868 the allies attacked López's last entrenched army at Lomas Valentinas, near Itá Ybaté. After days of fighting the Paraguayan positions were overrun, though López escaped with a small escort. The garrison of the riverside fort of Angostura, cut off, surrendered on 30 December, and the road to Asunción lay open. Caxias's call on López to surrender on 24 December had been refused.

  21. Allied troops occupy Asunción

    Brazilian troops entered the evacuated Paraguayan capital on 1 January 1869, and Caxias arrived on 5 January. About 30,000 allied soldiers were soon quartered there and looted almost every building. Caxias, ill, considered the war won and left; Brazil set up a provisional Paraguayan government, while López withdrew east into the hills of the Cordillera and raised a new army.

  22. Battle of Piribebuy

    Emperor Pedro II's son-in-law, the Count of Eu, took command in 1869 and led some 20,000 men into the Cordillera. On 12 August 1869 they stormed Piribebuy, López's temporary capital, defended by about 1,600 poorly armed men and boys. After five hours of fighting the town fell; its hospital was burned and the government's archives were lost. Some 730 of the defenders were killed.

  23. Battle of Acosta Ñu, the 'Children's Battle'

    Covering López's retreat on 16 August 1869, about 3,500 Paraguayans, most of them boys, faced more than 20,000 Brazilian and Argentine soldiers on the plain of Acosta Ñu. They were overwhelmed, with some 2,000 killed. It was the last major battle of the war, and Paraguay remembers it every 16 August as Children's Day. López himself escaped north with the survivors.

  24. López is killed at Cerro Corá and the war ends

    With a few hundred followers López retreated into the forests of the north-east, pursued by Brazilian columns. On 1 March 1870 troops under General José Antônio Correia da Câmara surprised his camp at Cerro Corá. López, wounded and refusing to surrender, was killed. Allied troops occupied Paraguay until 1876, and peace treaties gave disputed lands to Brazil and Argentina. He had refused every offer to surrender.

Related

Other wars of the time

Sources