Juan María Montalvo Fiallos (13 April 1832 - 17 January 1889) was an Ecuadorian essayist and novelist. His writing was strongly marked by anti-clericalism and opposition to presidents Gabriel García Moreno and Ignacio de Veintemilla. He was the publisher of the magazine El Cosmopolita. One of his best-known books is Las Catilinarias, published in 1880. His essays include Siete tratados (1882) and Geometría Moral (posthumous, 1902). He also wrote a sequel to Don Quixote de la Mancha, called Capítulos que se le olvidaron a Cervantes. He was admired by writers, essayists, intellectuals such as Jorge Luis Borges and Miguel de Unamuno. He died in Paris in 1889. His body was embalmed and is exhibited in a mausoleum in his hometown of Ambato.
