The military history of Argentina spans a period of over two centuries. During the course of those years, it broke colonial ties with Spain, waged a civil war to define its organization and wars with Brazil, Paraguay, Britain and France. The military also played a role in the institutional life of the country, during a series of coups d'état that took place in the 20th century.
Before independence.
One of the first notable military conflicts taking place in modern Argentina were the British invasions of the Río de la Plata, involving both Buenos Aires and Montevideo (currently part of Uruguay). As part of the Napoleonic Wars, a British force led by William Carr Beresford occupied Buenos Aires on June 27. The French Santiago de Liniers moved to Montevideo and led the forces that would reconquer Buenos Aires on August 12, 1806. The Viceroy Rafael de Sobremonte, who had fled from the city to Córdoba, was not allowed to return, and Liniers was trusted to organize the defense of the city against a possible British counter-attack. For this end he drafted all men capable to bear arms, regardless of their social condition (including slaves), and formed militias to defend the city. The Regiment of Patricians, composed of criollo people, was created during this time.
The second invasion took place the following year. A new British army, much bigger than the first one, invaded first Montevideo and then moved to Buenos Aires, led by Lieutenant-General John Whitelocke. The British found a strong resistance and were forced to surrender, and return Montevideo to the viceroyalty.
As a result of the invasions, Sobremonte was removed as viceroy, and replaced by Liniers. The Regiment of Patricians, led by Cornelio Saavedra, became a strong political force in Buenos Aires, and was instrumental to the failure of the Mutiny of Álzaga and the success of the May Revolution.
19th century.
War of independence.
The May Revolution ousted the Viceroy Baltasar Hidalgo de Cisneros and replaced him with a junta, the Primera Junta. The viceroyalty was also renamed, removing the "viceroyalty" word from it, and it nominally became the United Provinces of the Río de la Plata. However, the status of the different territories that used to belong to the viceroyalty changed many times during the development of the war, as some regions would remain loyal to the former organization, others were captured or recaptured, and later they would divide into several countries.
The first military campaigns against the royalists were waged by Manuel Belgrano and Juan José Castelli. The Army of the North led by Castelli was headed first by Ortiz de Ocampo and defeated a counter-revolution organized by Liniers at Córdoba. Castelli took command to enforce the execution of the captured royalists, and then moved to the Upper Peru. He took control of it for a brief time, and was defeated by Goyeneche at the Battle of Huaqui. Belgrano led an ill-fated campaign to Paraguay, and created the Flag of Argentina when preparing the defenses of Rosario against a possible attack from the Banda Oriental (where Montevideo was under siege by Artigas). Belgrano led a new campaign to the Upper Peru, achieving military victories at Salta and Tucuman, but being defeated at Vilcapugio and Ayohuma.
By this time José de San Martín arrived to Buenos Aires with other generals of the Peninsular War. They gave new strength to the Revolutionary war, which was compromised by the defeats of Belgrano and Castelli and the royalist resistance at the Banda Oriental. Alvear took Montevideo, and San Martín started a military campaign that would span across an important part of the Spanish territories in America. First, he created the Regiment of Mounted Grenadiers and defeated a Spanish raid at the Battle of San Lorenzo (the only battle that San Martín fought in Argentine territory). He created the Army of the Andes in Mendoza and, with help of Bernardo O'Higgins nd other Chileans he made the Crossing of the Andes and liberated Chile. With the Chilean navy at his disposal, he moved to Peru, liberating that country as well. San Martín met Simón Bolívar at Guayaquil, and retired from action.
The Congress of Tucumán was called while San Martín was preparing the crossing of the Andes. It declared independence from Spain or any other foreign power.
After independence.
After the Argentine independence from Spain, a history of military conscription emerged and that this tradition of mandatory military service began in 1896 with the First Conscription ("Servicio Militar Obligatorio") where 20-year-old men were drafted by a decree of President José Evaristo Uriburu and lasted until 1994. This policy persisted owing to numerous conflicts that Argentina was involved in previously after its independence and the foreseen territorial conflicts with neighboring countries. For instance, 1825 saw the outbreak of the Argentina-Brazil War over the control of Uruguay, then called "Banda Oriental". This war ended with the independence of Uruguay in 1828. The Argentine military achieved several victories against Brazil but internal political strife eventually forced them to withdraw and settle for the 1828 Convention of Peace, with the British serving as the intermediary.
Several years later, Argentina became involved in a conflict against the United Kingdom and France. This came with the November 20, 1845 Anglo-French blockade of the Río de la Plata. The combined forces from the United Kingdom and France seized control of the Paraná River in order to establish trade relationships with Paraguayan ports blocked by Argentina. The Army of the Argentine Confederation, commanded by General Lucio Mansilla, expelled the invaders causing severe damage to the 11 warships by shooting from both river's shores, at the cost of 150 Argentines killed and 90 wounded. Although the invading troops took fewer casualties (26 killed, 86 wounded), they decided to leave in order to preserve the remaining ships. It was the last attempt on Argentine rivers by the Royal Navy. Other notable conflicts include the following:
20th century.
From the latter part of the 19th century to the early 20th century, the Argentine military history was characterized by a process of armed forces modernization and technification. The following are key milestones during this period:
Postwar.
After the war, the military's role began to shift from the previous appearance as protector of the constitution and of the people against corruption. Military leaders during the postwar period began increasingly imposing their own rules and standards on the political system so that, in the end, the armed forces came to dominate the political system. This began during World War II, between 1939 and 1945. The civilian government considered joining the allies, but many officers in the armed forces and ordinary citizens objected due to fears over the spread of communism. This was a factor contributing to the military coup of 1943. Pedro Pablo Ramírez, who had been attached to the Kaiser's army and later Mussolini's in the twenties, became dictator. In 1944 he was replaced by Edelmiro Julián Farrell, who had spent two years attached to Mussolini's army. The government maintained a neutral policy but towards the end of the war, Farrell bowed to intense pressure from the United States. Like several Latin American states, Argentina made a late declaration of war against Germany.
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