The Treaty of Ancón was signed in the context of the War of the Pacific, which had begun in 1879 between Chile and the allied forces of Peru and Bolivia. The conflict largely revolved around control over valuable territories in the coastal regions, particularly those rich in nitrates. Following years of military engagements and conflicts, the Chilean forces emerged victorious, effectively altering the regional power dynamics. The treaty was signed by representatives from both countries in Ancón, Peru, and it marked the official cessation of hostilities between the two nations.

The treaty specifically stipulated that the province of Tarapacá, a primary area of contention due to its resource wealth, was to be ceded to Chile. This was a critical loss for Peru, underscoring the economic ramifications of the war. Additionally, the agreement articulated various conditions surrounding the treatment of prisoners and the resolution of outstanding issues post-conflict. The terms of the treaty, albeit creating a cessation of direct conflict, later contributed to tensions between Peru and Chile, particularly over further territorial claims in the region.

In the wake of the signing, relations between the South American nations evolved, leading to decades of diplomatic maneuvering and negotiation. The war and its aftermath reshaped national identities and territorial assertions in the region, solidifying Chile’s position as a dominant power in the Pacific while leaving Peru to reassess its territorial and national aspirations.