The Treaty of the Triple Alliance allied the Empire of Brazil, Argentina, and Uruguay against Paraguay. Signed in 1865, after the outbreak of the Paraguayan War, its articles (plus a Protocol) prescribed the allies' actions both during and after the war. An English translation of the text is reproduced in this article.
The war lasted until 1870 and led to the near-annihilation of Paraguay. After Paraguay's defeat, Brazil and Argentina, who were traditional enemies, hovered on the brink of mutual warfare for six years because of disputes and misunderstandings about the treaty.
According to article XVI Argentina was to receive a 600 km strip of territory in the Chaco north of the Pilcomayo River, nearly up to the Bolivian border. From the start the Brazilian government set out to frustrate the implementation of this particular stipulation, and eventually succeeded. Today this territory — the Central Chaco — belongs to Paraguay.
Background Although the Empire of Brazil and Argentina were traditional enemies, they, together with Uruguay, united against Paraguay in 1865. The Paraguayan War has been described by Leslie Bethell as "the bloodiest inter-state war anywhere in the world between the end of the Napoleonic Wars in 1815 and the outbreak of the First World War in 1914".
Its causes were various, and have been hotly disputed by modern writers; they have even been traced back to territorial disputes between Portugal and Spain stemming from the Treaty of Tordesillas (1494). "Indeed the Paraguayan War was just the last chapter in a two-century conflict between the Spanish and Portuguese over the region". But for the purposes of this article, it may be enough to outline the geopolitical situation and the immediate antecedents of the treaty.
Disputes over vital communications arteries
In the middle of the 19th century, vast tracts of South America were undeveloped, railways were few and short, and surfaced roads practically did not exist.Even in 1929 there were almost no paved or hard-surfaced roads in Argentina, outside of towns. Nearly all were dirt roads, originally created by oxcarts, impassable to motor vehicles after a single downpour: . So navigable rivers were "vital arteries". Of particular relevance were the Paraná and Paraguay rivers. Using the Paraná-Paraguay system, quite large ships could steam 1,870 miles (3,010 km) upriver from Buenos Aires well into the Brazilian Mato Grosso province. These rivers were of crucial importance to landlocked Paraguay,As late as 1960 Paraguay depended "almost completely on the Paraguay-Paraná rivers for the transport of freight" and its international trade: . to BrazilBy a geographical quirk, Brazil had no practical access to its Mato Grosso province – a land as big as Germany – except by the Paraná-Paraguay river route: . There was no railway link until the 1910s (). The overland journey from coastal Brazil ran through bad country and would have taken 3 months by horse-drawn cart: . It was far quicker to steam down the Atlantic, up the River Plate, and up the Paraná-Paraguay: ; . and to the trade of some Argentine provinces. It was, as wrote D.S. Chandler
Thus Buenos Aires Province under Juan Manuel de RosasRosas "viewed Paraguay as an errant province belonging to the orbit of Buenos Aires" (Williams 1979). had restricted river traffic to put pressure on upstream Paraguay, and Paraguay under Carlos Antonio López had done the same to put pressure on Brazil. In 1855 a Brazilian naval flotilla threatened Paraguay unless it conceded free navigation of the Upper Paraguay river.
In 1855 Paraguay, with an understandable fear and distrust of its neighbours, began to develop the formidable Fortress of Humaitá. Established near the mouth of the River Paraguay and known as the Gibraltar of South America, the fortress was the gateway to the country. However, it may have caused the Paraguayan government to feel itself invulnerable (wrongly, as it turned out), and it caused tension with Brazil. As explained by lieutenant colonel George Thompson of the Paraguayan Army:
Vessels bound for the Mato Grosso were subjected to bureaucratic harassment, Paraguay's object being to put pressure on Brazil to sign a boundary treaty defining their mutual frontiers. In 1858, however, Brazil explicitly threatened war unless these restrictions were removed, and Paraguay backed down.
Territorial disputes Furthermore, immense territories were disputed. Not effectively occupied by anyone, except the aboriginal inhabitants, they had no obvious international boundaries. There was a boundary dispute between Brazil and Paraguay going back to colonial times, and there were large areas in dispute between Paraguay and Argentina in the Gran Chaco and in the territory of Misiones. Then, there were no obvious and accepted principles according to which they might have been resolved, and no established practice of international arbitration existed. In international law victory in war was a recognised way of acquiring territory.
Although the Paraguayan War only partly originated in boundary disputes, according to American historian Thomas L. Whigham their existence "always added to the climate of mistrust in the region and made a violent clash on a large scale as likely as anything in history can be".
Paraguayan military buildup
Between 1854 and 1864, and supervised by Francisco Solano López, Carlos Antonio López's son, Paraguay built up its military forces because it thought that the outside world (in particular Brazil, Argentina, the United States, and the British Empire) was disrespecting it. Paraguay imported some 200 foreign technicians, mostly British, and developed an iron foundry, an arsenal, a shipyard, a telegraph and a railway. This modernisation was military-oriented."Though unique in many respects, the government's industrialization program was strictly limited to military concerns and could do little to create the infrastructure necessary for 'a new Paraguay'": It also imported from Britain the cadre of a military medical corps who trained Paraguayan medical students. Thus Paraguay became an important regional power. However, as noted by John Hoyt Williams, "the dizzying speed with which his nation was 'modernized' and strengthened tempted López to flex his new muscle and seek an ever-expanding, activist role in international affairs". López became ruler of Paraguay in September 1862 after the death of his father.
Intrigues A focus of instability was the small Republic of Uruguay, which had achieved independence in 1828. Wrote Professor Whigham:
In 1862 the Blanco faction, traditionally hostile to Brazil, and now alarmed because its bitter enemiesThere were frequent civil wars between the Blancos and Colorados of Uruguay, rival Argentine political factions backing each side. Likewise, rival Uruguayan factions supplied military support to each side in the Argentine civil wars. Wrote Pelham Horton Box: "Blancos and Colorados were in the habit of transferring their immense hatreds to the larger stage of the distracted Argentine Confederation... After a battle between the Argentine parties their Uruguayan allies would seek each other out for purposes of massacre and outrage... The connection between Argentines and Uruguayans was so close that in the wars of either country the principal chiefs of each fought or struggled in co-operation". () had seized power in Buenos Aires too, (They won the Battle of Pavón). felt itself to be acutely short of allies. It began a covert diplomatic campaign to turn upriver Paraguay aggressivelyUnder the regimes of José Gaspar Rodríguez de Francia and Carlos Antonio López, Paraguay's attitude to Buenos Aires, though usually unfriendly, was always firm, cautious and defensive. Thus Paraguay's traditional policy was to keep out of regional disputes. against Buenos Aires.
This campaign, which continued through 1864, insinuated that Buenos Aires had designs on both Paraguay and Uruguay, who should make a warlike alliance, detach the Argentine provinces of Corrientes and Entre Ríos and seize Martín García Island. Although Francisco Solano López of Paraguay did not trust the Blancos and did not sign an alliance with Uruguay, he nevertheless built up his strength. Because women had always grown the subsistence crops in Paraguay, all able bodied men aged 16–50 were available for service and, in March 1864, they were conscripted for "intensive" military training.It was so intensive that, according to George Thompson (who became a lieutenant colonel in the Paraguayan army), 6,000 men died on these manoeuvres:
By September 1864 López had an estimated 48,000–150,000 men on a war footing, more than any other power in the region."While Brazil had a huge national guard, that force was poorly equipped, untrained, and effectively useless – when the war began, the government created a new army rather than rely on the guard – and the standing army was a small, ill-trained force that consisted largely of press-ganged vagrants: . In 1864 the Argentine army was not even strong enough to protect frontier communities from Indian raids: For Whigham, "Paraguay was the only country in the region that could boast of its military preparedness and a full treasury".
Paraguay invades two Brazilian provinces
However, as events transpired, López did not launch this force on Argentina, but on Brazil. In northern Uruguay lived many who claimed Brazilian nationality, and Brazil complained these people were being mistreated with the connivance of Uruguay's ruling Blanco party: it was a long-standing grievance, and serious atrocities were alleged.About 10% of Uruguayan residents were (or claimed to be) Brazilian nationals (). Northern Uruguay was a lawless area and there were frequent complaints of beheadings, burnings, forced conscriptions, and other atrocities. Brazil complained that the Uruguayan government did not do enough to prevent them, indeed that some officials were complicit: . In April 1864 political agitation brought Brazilian anger to the boil. In May 1864 Brazil sent a diplomatic mission to Uruguay to demand reparations, accompanied by a naval squadron; Brazilian troops massed along the border. On 30 August 1864 Paraguay warned Brazil against military action in Uruguay, but this was ignored: the Uruguayan War began. In November 1864, Paraguay fired upon and seized the Brazilian government ship Marquês de Olinda as it was steaming up the River Paraguay on its routine monthly voyage to the Mato Grosso. It proved to be carrying military stores. Paraguayan armies proceeded to invade the Brazilian province of Mato Grosso. Later, they invaded Rio Grande do Sul.
Paraguay invades an Argentine province Paraguay, difficult of access, might have resisted Brazilian retaliation for a long time, but now it took a step that was to give Brazil what it had lacked hitherto: a good forward base from which to attack it. It did so by invading Argentina. First, on 14 January 1865, the Paraguayan government asked Argentina for permission to attack Brazil across the Corrientes Province, which was refused. On 13 April, Paraguayan ships fired upon and seized two Argentine naval vessels moored in the Argentine port of Corrientes and the Paraguayans proceeded to invade the province itself. It prompted the alliance with Brazil.
Upshot Paraguay had now made war on the much more populous Empire of Brazil, on Argentina (also more populous),Before the war Brazil's population was about 10 million; Argentina's, about 1.5 million; Paraguay's, possibly 300–400,000: and threatened the Colorado faction of Uruguay, which by now had come into power. The three countries had been accustomed to thinking about Paraguay as a backward upstart and were outraged. Their foreign ministers met in Buenos Aires and negotiated the Treaty of the Triple Alliance.
Negotiations