Chile–Peru relations and Angamos (Oct. 8, 1879) enabled Chile to control the sea approaches to Peru. A Chilean army then invaded Peru. An attempt at mediation by the United States failed in October 1880, and Chilean forces occupied the Peruvian capital of Lima the following January. Chile was also to occupy the provinces of Tacna and Arica for 10 years, after which a plebiscite was to be held to determine their nationality. But the two countries failed for decades to agree on what terms the plebiscite was to be conducted. This diplomatic dispute over Tacna and Arica was known as the Question
Viceroyalty of Peru on July 21, 1821. The independence of Peru was proclaimed on July 28, 1821. Viceroy José de la Serna e Hinojosa, still in command of a sizable military force, retired to Jauja, and later to Cusco. On July 26, 1822, San Martín and Simón Bolívar met in Guayaquil to define a strategy for the liberation of the rest of Peru. The meeting was secret, and exactly what occurred is not known. However, afterwards San Martín returned to Argentina while Bolívar prepared to launch an offensive against the remaining royalist forces in Peru and Upper Peru (Bolivia). In September 1823 Bolívar