The War of the Pacific breaks out when the Chilean Army occupies the Bolivian port city of Antofagasta.

The War of the Pacific, also known by multiple other names, was a war between Chile and a Bolivian–Peruvian alliance from 1879 to 1884. Fought over Chilean claims on coastal Bolivian territory in the Atacama Desert, the war ended with victory for Chile, which gained a significant amount of resource-rich territory from Peru and Bolivia.

The Chilean Army is the land arm of the Chilean Armed Forces. This 80,000-person army is organized into six divisions, an army aviation brigade and a special operations brigade.

Bolivia, officially the Plurinational State of Bolivia, is a landlocked country located in central South America. The country features diverse geography, including vast Amazonian plains, tropical lowlands, mountains, the Gran Chaco Province, warm valleys, high-altitude Andean plateaus, and snow-capped peaks, encompassing a wide range of climates and biomes across its regions and cities. It includes part of the Pantanal, the largest tropical wetland in the world, along its eastern border. It is bordered by Brazil to the north and east, Paraguay to the southeast, Argentina to the south, Chile to the southwest, and Peru to the west. The seat of government is La Paz, which contains the executive, legislative, and electoral branches of government, while the constitutional capital is Sucre, the seat of the judiciary. The largest city and principal industrial center is Santa Cruz de la Sierra, located on the Llanos Orientales, a mostly flat region in the east of the country with a diverse non-Andean culture.

Antofagasta is a port city in northern Chile, about 1,100 kilometres (700 mi) north of Santiago. It is the capital of Antofagasta Province and Antofagasta Region. According to the 2015 census, the city has a population of 402,669.