section_path: History/Wars and conflicts
section_name: Wars and conflicts
paragraph_text: Wars and conflicts
  
  Despite the Spanish American wars of independence and the Brazilian War of Independence, the new nations quickly began to suffer with internal conflicts and wars among themselves. Most of the 1810 borders countries had initially accepted on the uti possidetis iuris principle had by 1848 either been altered by war or were contested.
  
  In 1825, the proclamation of independence of Cisplatina led to the Cisplatine War between historical rivals the Empire of Brazil and the United Provinces of the Río de la Plata, Argentina's predecessor. The result was a stalemate, ending with the British government arranging for the independence of Uruguay. Soon after, another Brazilian province proclaimed its independence leading to the Ragamuffin War which Brazil won.
  
  Between 1836 and 1839, the War of the Confederation broke out between the short-lived Peru-Bolivian Confederation and Chile, with the support of the Argentine Confederation. The war was fought mostly in the actual territory of Peru and ended with a Confederate defeat and the dissolution of the Confederacy and annexation of many territories by Argentina.
  
  Meanwhile, the Argentine Civil Wars plagued Argentina since its independence. The conflict was mainly between those who defended the centralization of power in Buenos Aires and those who defended a confederation. During this period it can be said that "there were two Argentines": the Argentine Confederation and the Argentine Republic. At the same time, the political instability in Uruguay led to the Uruguayan Civil War among the main political factions of the country. All this instability in the platine region interfered with the goals of other countries such as Brazil, which was soon forced to take sides. In 1851, the Brazilian Empire, supporting the centralizing unitarians, and the Uruguayan government invaded Argentina and deposed the caudillo, Juan Manuel Rosas, who ruled the confederation with an iron hand. Although the Platine War did not put an end to the political chaos and civil war in Argentina, it brought temporary peace to Uruguay where the Colorados faction won, supported by Brazil, Britain, France and the Unitarian Party of Argentina.
  
  Peace lasted only a short time: in 1864, the Uruguayan factions faced each other again in the Uruguayan War. The Blancos supported by Paraguay started to attack Brazilian and Argentine farmers near the borders. The Empire made an initial attempt to settle the dispute between Blancos and Colorados without success. In 1864, after a Brazilian ultimatum was refused, the imperial government declared that Brazil's military would begin reprisals. Brazil declined to acknowledge a formal state of war, and, for most of its duration, the Uruguayan–Brazilian armed conflict was an undeclared war which led to the deposition of the Blancos and the rise of the pro-Brazilian Colorados to power again. This angered the Paraguayan government, which even before the end of the war invaded Brazil, beginning the longest and bloodiest inter-state war in Latin American history: the Paraguayan War.
  
  The Paraguayan War began when the Paraguayan dictator Francisco Solano López ordered the invasion of the Brazilian provinces of Mato Grosso and Rio Grande do Sul. His attempt to cross Argentinian territory without Argentinian approval led the pro-Brazilian Argentine government into the war. The pro-Brazilian Uruguayan government showed its support by sending troops. In 1865 the three countries signed the Treaty of the Triple Alliance against Paraguay. At the beginning of the war, the Paraguayans took the lead with several victories, until the Triple Alliance organized to repel the invaders and fight effectively. This was the second total war experience in the world after the American Civil War. It was deemed the greatest war effort in the history of all participating countries, taking almost 6 years and ending with the complete devastation of Paraguay. The country lost 40% of its territory to Brazil and Argentina and lost 60% of its population, including 90% of the men. The dictator Lopez was killed in battle and a new government was instituted in alliance with Brazil, which maintained occupation forces in the country until 1876.
  
  The last South American war in the 19th century was the War of the Pacific with Bolivia and Peru on one side and Chile on the other. In 1879 the war began with Chilean troops occupying Bolivian ports, followed by Bolivia declaring war on Chile which activated an alliance treaty with Peru. The Bolivians were completely defeated in 1880 and Lima was occupied in 1881. Peace was signed with Peru in 1883 while a truce was signed with Bolivia in 1884. Chile annexed territories of both countries leaving Bolivia landlocked.
  
  In the new century, as wars became less violent and less frequent, Brazil entered into a small conflict with Bolivia for the possession of the Acre, which was acquired by Brazil in 1902. In 1917 Brazil declared war on the Central Powers, joined the allied side in the First World War and sent a small fleet to the Mediterranean Sea and some troops to be integrated with the British and French forces in the region. Brazil was the only South American country that participated in the First World War. Later in 1932 Colombia and Peru entered a short armed conflict for territory in the Amazon. In the same year Paraguay declared war on Bolivia for possession of the Chaco, in a conflict that ended three years later with Paraguay's victory. Between 1941 and 1942 Peru and Ecuador fought for territories claimed by both that were annexed by Peru, usurping Ecuador's frontier with Brazil.
  
  Also in this period, the first major naval battle of World War II took place in the South Atlantic close to the continental mainland: the Battle of the River Plate, between a British cruiser squadron and a German pocket battleship. The Germans still made numerous attacks on Brazilian ships on the coast, causing Brazil to declare war on the Axis powers in 1942, being the only South American country to fight in this war (and in both World Wars). Brazil sent naval and air forces to combat German and Italian submarines off the continent and throughout the South Atlantic, in addition to sending an expeditionary force to fight in the Italian Campaign.
  
  A brief war was fought between Argentina and the UK in 1982, following an Argentine invasion of the Falkland Islands, which ended with an Argentine defeat. The last international war to be fought on South American soil was the 1995 Cenepa War between Ecuador and the Peru along their mutual border.