Historia del reinado de Fernando e Isabel, los Reyes Católicos

(fist published 1837; new revised ed. London, 1892; Span. transl. 2002-2004)

Under the influence of George Ticknor, a friend and mentor who taught European literature at Harvard, Prescott began learning Spanish in 1824. Engrossed by the history of Spain, he committed himself to tracing its development into a world power. Employing secretaries to read him manuscripts sent from Spanish archives, Prescott set about writing a work of sound scholarship that would also interest a general audience. A phenomenal memory allowed him to compose whole chapters in his mind during morning horseback rides. Later he recorded them on paper using a noctograph, a special stylus for the blind. More than a decade later he finished "The History of the Reign of Ferdinand and Isabella the Catholic"(1837), which enjoyed tremendous critical and popular success on both sides of the Atlantic.

Prescott’s fame gained him entrée into Spanish intellectual circles, greatly facilitating research on his next book, History of the Conquest of Mexico (1843), a sweeping account of Cortés’s subjugation of the Aztec people.