Chaco War
The Chaco War was fought from 1932 to 1935. It was between Bolivia and Paraguay over control of the northern part of the Gran Chaco region, which was thought to be rich in petroleum. The war is also referred to as La Guerra de la Sed, since it was fought in the semi-arid Chaco. It was the first South America war in which modern weapons were used, and also the bloodiest South America war of the 20th century — around 2% of the Bolivian population and 3% of Paraguayans were killed during the conflict.
During the war, both landlocked countries faced difficulties moving arms and supplies through neighbouring countries. Despite its income from mining and a larger and better-equipped army, problems with international trade and poor internal communications ultimately turned the tide against Bolivia. The war concluded at the Chaco Peace Conference in Buenos Aires in July 1938, at which both countries signed a peace treaty awarding three-quarters of the Gran Chaco to Paraguay.
Origins
The origins of the war are attributed to a long-standing territorial dispute and to the discovery of oil deposits on the eastern Andes range. After losing territory to neighboring countries in the late 19th century, both Bolivia and Paraguay had become landlocked countries. The Chaco was sparsely populated, but control of the Paraguay River running through it would provide access to the Atlantic Ocean. Paraguay had lost almost half of its claimed territory to Brazil and Argentina as a consequence of the War of the Triple Alliance, and its economic viability depended on retaining control of the Paraguay River. In 1879, Bolivia lost its Pacific coast to Chile during the War of the Pacific. The 1929 Treaty of Lima ended the hopes of the Bolivian government of recovering a land corridor to the Pacific Ocean, so Bolivia viewed access to the Atlantic Ocean via the Paraguay River as imperative to international trade and further economic development.In international arbitration, Bolivia argued that the region had been part of the original Spanish colonial province of Moxos and Chiquitos to which Bolivia was heir. Meanwhile, Paraguay based its case on the occupation of the land. Indeed, both Paraguayan and Argentine ranchers were already breeding cattle and exploiting the quebracho forests in the area, and the small population of nomadic indigenous Guaraní-speaking people was related to Paraguay's own Guaraní heritage. As of 1919, Argentine banks owned of land in the eastern Chaco, and the Casado family, a powerful part of the Argentine oligarchy, held 141,000. The presence of Mennonite colonies in the Chaco, who settled there in the 1920s under the auspices of the Paraguayan government, was another factor in favour of Paraguay's claim.
The impetus for war was exacerbated by a conflict between oil companies jockeying for exploration and drilling rights, with Royal Dutch Shell backing Paraguay and Standard Oil Company supporting Bolivia. The discovery of oil in the Andean foothills sparked speculation that the Chaco might prove to be a rich source of petroleum. Standard Oil was already producing oil from wells in the hills of eastern Bolivia, around Villamontes. In addition to the interests of these companies, Argentina's goal of importing petroleum from the Chaco also contributed to the instigation of the war. In opposition to the "dependency theory" of the war's origins, the British historian Matthew Hughes argued against the thesis that Bolivian and Paraguayan governments were the "puppets" of Standard Oil and Royal Dutch Shell respectively by writing: "In fact, there is little hard evidence available in the company and government archives to support the theory that oil companies had anything to do with causing the war or helping one side or the other during the war". The historian Bret Gustafson, on the other hand, argues that "the blurred lines between the bank and the oil industry show that did indeed finance the Bolivian build-up, even if instigating the war was left to Bolivian generals."
Prelude to war
The first confrontation between the two countries dates back to 1885, when Bolivian president Gregorio Pacheco founded Puerto Pacheco, a port on the Upper Paraguay River, asserting that this new settlement was well inside Bolivian territory. In 1888, the Paraguayan government sent the gunboat Pirapó, commanded by Paraguayan War veteran Domingo Antonio Ortiz, which forcibly evicted the Bolivians from the settlement. Two agreements followed, in 1894 and 1907, which neither the Bolivian nor the Paraguayan government approved. Meanwhile, in 1905, Bolivia — ignoring Paraguayan official protests — founded Ballivián and Guachalla, two new outposts along the Pilcomayo River in the Chaco.Bolivian penetration in the region went unopposed until 1927, when the first blood was shed over the Gran Chaco. On 27 February, members of a Paraguayan Army foot patrol were taken prisoner near the Pilcomayo River and held in the Bolivian outpost of Fortín Sorpresa, where the commander of the Paraguayan detachment, Lieutenant Adolfo Rojas Silva, was shot and killed in suspicious circumstances. Fortín was the name used for the small pillbox and trench-like garrisons constructed by the military forces in the Chaco. The Bolivian government formally regretted the death of Rojas Silva, but Paraguayan public opinion called it "murder". After subsequent talks in Buenos Aires failed to produce any agreement in January 1928, the dispute grew more violent. On 5 December 1928, a Paraguayan cavalry unit overran Fortín Vanguardia, an advance outpost established by the Bolivian army a few kilometres northwest of Bahía Negra. The Paraguayans captured 21 Bolivian soldiers and burned their huts to the ground.
On 14 December 1928, Bolivia retaliated by capturing Fortín Boquerón, killing 15 Paraguayans. The Bolivians also conducted an air strike on Bahía Negra on 15 December, which caused few casualties and little damage. A return to the status quo ante bellum was eventually agreed on 12 September 1929 in Washington, DC, under pressure from the Pan American League, but an arms race had already begun, and both countries were on a collision course. The regular border clashes might have led to war in the 1920s if either side had been capable of waging war. However, neither Paraguay nor Bolivia had an arms industry, and both countries had to import vast quantities of arms from Europe and the United States to arm themselves for the coming conflict. It was this lack of sufficient arms that delayed the outbreak of the war until 1932.
Armies
Bolivian infantry forces were armed with the latest in foreign weapons, including DWM Maxim M1904 and M1911 machine guns, Czechoslovak ZB vz. 26 and Vickers-Berthier light machine guns, Mauser-type Czechoslovak Vz. 24 7.65 mm rifles and Schmeisser MP-28 II 9 mm submachine guns. At the outset, the Paraguayan troops used a motley collection of small arms, including the German Maxim, the British Vickers, the Browning MG38 water-cooled machine guns, and the Danish Madsen light machine gun. The primary service rifle was the M1927 7.65 mm Paraguayan Long Rifle, a Mauser design based on the M1909 Argentine Long Rifle and manufactured by the Oviedo arsenal in Spain. The M1927 rifle, which tended to overheat in rapid fire, proved highly unpopular with the Paraguayan soldiers. Some M1927 rifles experienced catastrophic receiver failures, a fault that was later traced to faulty ammunition. After the commencement of hostilities, Paraguay captured sufficient numbers of Bolivian VZ-24 rifles and MP 28 submachine guns to equip all of its front-line infantry forces.Paraguay had a population only a third as large as that of Bolivia. However, Paraguay gained the upper hand because of its innovative style of fighting, centered on rapid marches and flanking encirclements, compared to Bolivia's more conventional strategy. In June 1932, the Paraguayan Army totaled about 4,026 men. Both racially and culturally, the Paraguayan Army was practically homogeneous. Almost all of its soldiers were European-Guaraní mestizos. Bolivia's army, however, were mostly descended from the Altiplano's aboriginals of Quechua or Aymará, while the lower-ranking officers were of Spanish or other European ancestry, and the army commander-in-chief, Hans Kundt, was German. Although the Bolivian army had more manpower, it never mobilized more than 60,000 men, and no more than two-thirds of its army were ever on the Chaco. Paraguay, on the other hand, mobilized its entire army. A British diplomat reported in 1932 that the average Bolivian had never been anywhere close to the Chaco and "had not the slightest expectation of visiting it in the course of his life." Most Bolivians had little interest in fighting, let alone dying, for the Chaco. Furthermore, the typical Bolivian soldier was a Quechua or Aymara peasant conscript accustomed to life high in the Andes Mountains and did not fare well in the low-lying, hot, and humid land of the Chaco.
Many Paraguayan Army commanders had gained combat experience as volunteers with the French Army in World War I. Its army commander, Colonel José Félix Estigarribia, soon rose to the top of the combat command. Estigarribia capitalized on the native Guarani knowledge of the forest and ability to live off the land to gain valuable intelligence on conducting his military campaigns. Estigarribia preferred to bypass Bolivian garrisons, and his subordinates, such as Colonel Rafael Franco, proved adept at infiltrating enemy lines often by encircling Bolivian strongholds. Both sides resorted to entrenched strongpoints and used barbed wire, mortars, machineguns, and mines with interlocking fields of fire.
Paraguay's war effort was total. Buses were commandeered to transport troops, wedding rings were donated to buy weapons, and Paraguay had by 1935 widened conscription to include 17-year-olds and policemen. Perhaps the most important advantage enjoyed by Paraguay was that the Paraguayans had a rail network running to the Chaco with five narrow-gauge railroads totaling some running from the ports on the Paraguay River to the Chaco, which allowed the Paraguayan Army to bring men and supplies to the front far more effectively than the Bolivians ever managed. In 1928, the British legation in La Paz reported to London that it took the Bolivian Army two weeks to march their men and supplies to the Chaco and that Bolivia's "inordinately long lines of communication" would help Paraguay if war broke out. Furthermore, the drop in altitude from in the Andes to in the Chaco imposed further strain on Bolivia's efforts to supply its soldiers in the Chaco. Bolivia's railroads did not run to the Chaco, and all Bolivian supplies and soldiers had to travel to the front on badly-maintained dirt roads. Hughes wrote that the Bolivian elite was well aware of the logistical problems but that throughout the war, Bolivia's leaders had a "fatalistic" outlook. It took for granted that the fact that the Bolivian Army had been trained by a German military mission whilst the Paraguayan Army had been trained by a French military mission, together with the tough nature of their Quechua and Aymara Indian conscripts and the country's will to win and determination, would give them the edge in the war.
Both armies deployed a significant number of cavalry regiments, but they actually served as infantry since it was soon learned that the dry Chaco could not provide enough water and forage for horses. Only a relatively few mounted squadrons carried out reconnaissance missions at the divisional level.