In 1560, General Pedro de Urs a led an expedition through the Amazon in search of El Dorado. Three months later, Urs a was murdered. His replacement, Fernando de Guzm n, was also murdered. Emerging from the chaos was the Biscayan Lope de Aguirre, who turned away from El Dorado and led his men to Peru to overthrow the royal forces and declare independence from the Spanish Crown. When Aguirre was finally killed, the aftermath was astonishing: hundreds...