Why did Chile fight the War of the Pacific against Peru and Bolivia?

The War of the Pacific (1879–1883) was primarily driven by territorial and economic disputes over the Atacama Desert, a region rich in valuable sodium nitrate deposits.

The conflict originated from tensions between Chile and Bolivia regarding the control and taxation of mining operations in the desert, which were largely managed by Chilean and British interests. Although a treaty had established boundaries and tax-sharing agreements, relations deteriorated when Bolivia attempted to increase taxes on the Chilean Antofagasta Nitrate Company in 1878. When Bolivia threatened to confiscate the company's property, Chilean forces occupied the port of Antofagasta in February 1879.

Bolivia declared war and invoked a secret 1873 mutual defense pact with Peru, which also sought to challenge Chile’s growing influence on the Pacific coast. Consequently, Chile declared war on both nations. The conflict resulted in a decisive Chilean victory, leading to the annexation of the Bolivian coastal region and the Peruvian province of Tarapacá, effectively leaving Bolivia landlocked.12