 Abaroa was an engineer by trade, working in a silver mine located in the coastal region of Litoral, which Chile took from Bolivia during the War of the Pacific.During the Battle of Topáter (23 March 1879), the first armed clash of the war, Colonel Abaroa was part of a badly outnumbered Bolivian force defending a bridge that crossed the Topáter River and gave access to the city of Calama, an important desert oasis on the road to Bolivia.Refusing to surrender, after the outnumbered Bolivian military forces withdrew, he fought to his last breath, a feat that later transformed him into a revered national hero.