This article examines the life and work of Mary J. Serrano (1840-1923), a successful translator and popularizer of Spanish literature in late nineteenth-century United States. It provides a short biography of Serrano and focuses on her work for the Spanish Legation in in Washington D.C. during the Cuban War of Independence (1895-98), a period of increasing anti-Spanish sentiment in the country. The article seeks to recover the figure of this important, yet largely unknown translator. Her biography also illuminates a number of trends that helped define this moment in history: the bourgeoning role of women as translators and authors, but also cultural mediators and engaged citizens; the diffusion and popularization of the emerging field of Hispanism in the United States; and the complex web of interactions and ethnic identities that shaped the immigrant experience in urban America.