The Spanish American wars of independence were a series of conflicts fought across Spanish America in the early nineteenth century that ended Spain's colonial rule over the mainland of the Americas, a possession it had held for roughly three centuries.
The crisis that made those wars possible began in Europe: Napoleon's invasion of Spain in 1808 forced the abdication of King Ferdinand VII and installed Napoleon's own brother on the Spanish throne, throwing the legitimacy of royal authority over the American colonies into open question. Independence movements led by figures including Simon Bolivar, whose campaigns liberated Venezuela, Colombia, Ecuador, Peru and the country later named Bolivia in his honour, and Jose de San Martin, who led the liberation of Argentina and Chile before joining the campaign in Peru, fought Spanish royalist forces across the continent for close to two decades.
By 1826 nearly all of mainland Spanish America had won its independence, a process effectively decided by the Battle of Ayacucho in December 1824, which broke the last major Spanish royalist army in South America. The wars left a patchwork of new republics whose borders largely followed old Spanish colonial administrative divisions rather than any natural political unity, a legacy of fragmentation that shaped much of the region's subsequent history of internal conflict.