Treaty of Ancón

The Treaty of Ancón was signed by Peru and Chile on  20 October 1883, in the Ancón District near Lima. It was intended to settle the two nations' remaining territorial differences at the conclusion of their involvement in the War of the Pacific and to stabilise post-bellum relations between them.Under the treaty's terms, Chile gained control over the province of Tarapacá. Chile was also to occupy the provinces of Tacna and Arica for ten years, after which a plebiscite would be organised to determine their nationality. However, for several decades following the two countries were unable to reach agreement on the terms the plebiscite.
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