Like most wars before and since, The War of the Pacific (1879 - 1883) was about money: nitrate and guano deposits (both of which were used in fertilizers) in the Atacama Desert, in this case. Although Peru and Bolivia owned the land where most of the nitrate mines were, the mines themselves were owned and operated by Chile. This lead to disputes about taxes, which in turn resulted in a full blown war between Chile on the one side and Peru and Bolivia on the other.
The war started off slowly, but once Chile had mobilized their navy they quickly established supremacy over the more primitive Peruvian and Bolivian forces. The subsequent land battle was short-lived, especially for Bolivia who surrendered as early as 1880. Peru hung on for longer, and Chilean forces got as far as Lima, which they occupied in 1881. Two years of guerrilla warfare followed, but eventually a treaty was signed in 1883.
Not only were 13 000 lives lost, but both Peru and Bolivia ceded huge swathes of territory to Chile. Chile gained enormously from the war and Peru suffered badly but perhaps the biggest losses were Bolivian – they gave up all of their coastal territories, including the major port of Antofagasta, in the war and have been landlocked ever since.
One of Chile’s biggest heroes of this war, Arturo Prat, has the honour of being the man with the most Chilean streets named after him: there are 162 communes in Chile which have a street bearing his name.
In Lima, the Parque de la Reserve was built to commemorate the occupation of Lima and boasts a small on-site museum. Most people, however, go to see the Magic Water Circuit - an incredible display of 13 interactive fountains which has nothing to do with the war.
The cover photo of this post shows the monument at Alto de la Alianza near Tacna in Peru. This was the site of one of the war's most important battles.