The Atacama Desert is the driest place on Earth and was, in the 1870s, one of the most valuable: its crust held the world’s supply of sodium nitrate — saltpeter — the fertilizer and explosive feedstock of the industrial age. The deposits lay in Bolivia’s coastal province and Peru’s Tarapacá, but the capital, railways, and labour working them were largely Chilean, and Peru and Bolivia had a secret alliance against their pushy southern neighbour.
The fuse was a tax: ten centavos per quintal, levied by Bolivia on a Chilean nitrate company in breach (Chile held) of treaty. When the company refused and Bolivia moved to auction its assets, Chilean troops landed at Antofagasta on 14 February 1879 — the day of the auction. Declarations of war followed within weeks.
Grau and Prat
The war’s opening act made both navies’ legends. At Iquique on 21 May 1879, the Peruvian ironclad Huáscar under Miguel Grau sank the wooden corvette Esmeralda, whose captain Arturo Prat leapt aboard the enemy deck with sword drawn and died there — instantly Chile’s supreme national hero, his name now on avenues in every Chilean town. Grau, “the Gentleman of the Seas,” fished Chilean survivors from the water and mailed Prat’s effects to his widow with a letter of condolence; Chile hunted the Huáscar for five months and killed him at Angamos in October. With the sea won, Chilean armies took the nitrate provinces, then Tacna and Arica, and in January 1881 — after the bloody battles of Chorrillos and Miraflores — occupied Lima itself, holding the Peruvian capital for nearly three years while guerrilla war ground through the sierra.
The Treaty of Ancón (1883) and a truce with Bolivia (1884) delivered the spoils: Chile kept Tarapacá and, ultimately, Antofagasta — the nitrate revenues funded the Chilean state for a generation, until synthetic nitrates (a German wartime invention) gutted the industry after 1918.
The sea
Bolivia’s loss was categorical: its entire 400-kilometre coastline, confirmed by treaty in 1904 in exchange for a railway and transit rights. The wound never closed. Bolivia maintains a navy — training on Lake Titicaca, 3,800 metres up — celebrates an annual Day of the Sea complete with the cry “¡Viva el Litoral!”, and pursued Chile at the International Court of Justice, which ruled in 2018 that Chile is under no obligation to negotiate sovereign access. The Atacama’s nitrate towns are ghost settlements now, picked over by tourists; the map they redrew, and the landlocked republic they left behind, are the war’s permanent monuments.