A period of political and economic instability in the early-to-mid-19th century weakened Bolivia. In addition, during the War of the Pacific (1879–83), Chile occupied vast territories rich in natural resources south west of Bolivia, including the Bolivian coast. Chile took control of today's Chuquicamata area, the adjoining rich ''salitre'' (saltpeter) fields, and the port of Antofagasta among other Bolivian territories.