Which territories did Chile annex after the War of the Pacific?

Following the War of the Pacific (1879–1883), Chile significantly expanded its territory by annexing regions rich in mineral resources, particularly sodium nitrate.1

The territories acquired by Chile included:

• Antofagasta: Chile occupied this Bolivian coastal province during the war. A truce in 1884 granted Chile control of the entire region, and a 1904 treaty made this annexation permanent.1
• Tarapacá: Under the Treaty of Ancón signed in 1883, Peru ceded the province of Tarapacá to Chile.1
• Arica: While the status of Tacna and Arica remained a long-standing diplomatic dispute known as the Question of the Pacific, a 1929 accord ultimately resulted in Chile retaining control of Arica, while Tacna was returned to Peru.1

Although Chile initially occupied the province of Tacna as well, it was not permanently annexed, as it was returned to Peru following the 1929 settlement.1