Independence

Uprisings against the Spanish colonial governments became frequent toward the end of the 18th century. Most were led by creoles, who resented Spain's tight control over the economy and politics. By 1810, revolutionary movements were under way in most of Spanish South America. Complete independence was finally achieved in 1825, after a series of bloody wars. The two great leaders of the revolution were Simón Bolívar and José de San Martín.

Brazil achieved independence from Portugal in 1822, almost without bloodshed. England, France, and Holland continued to hold their small colonies.

Simón Bolívar envisioned a confederation of all of Spanish South America. All efforts at consolidation failed, however, and nine weak nations were carved out of the three Spanish viceroyalties. Many boundary disputes erupted among the new nations, with some leading to war.

The Argentine-Brazilian War (1825–28) was fought over Uruguay, which both countries claimed. Through British mediation, the war ended in recognition of Uruguay as an independent country.

The War of the Peru-Bolivian Confederation (1837–39) was caused by the political union of Peru and Bolivia. Chile felt threatened and declared war, which ended in the defeat of the confederation.

The War of the Triple Alliance (1865–70) was fought by Argentina, Brazil, and Uruguay against Paraguay, which was threatening the political stability of the region. The war ended with the crushing defeat of Paraguay.

The War of the Pacific (1879–83), in which Peru and Bolivia were allied against Chile, was fought for control of the mineral-rich Atacama Desert. Peru and Bolivia were defeated, and Bolivia was deprived of an outlet to the Pacific Ocean.

The Chaco War (1932–35) was fought by Bolivia and Paraguay over the long-disputed Chaco territory. Paraguay won most of the disputed area, but under the terms of the 1938 peace treaty Bolivia was provided with an outlet to the Atlantic Ocean.

Peruvian-Ecuadorian Border Disputes have occurred frequently; Ecuador lost some territory in 1942, following one serious dispute.