Following the War of the Pacific (1879-1883), Chile and Peru signed the Treaty of Anc n (1884) that, in part, dealt with settling a territorial dispute over the provinces of Tacna and Arica along the countries' new common border. The treaty allowed Chile to administer the two provinces for a period of ten years, after which a plebiscite would allow the region's inhabitants to determine their own nationality. At the end of the prearranged decade, however,...