José S. (José Sixto) Alvarez

Born in Gualeguaychú, Entre Ríos, in 1858, José Sixto Álvarez wrote under the better-known pen name Fray Mocho. He worked as a journalist and became admired for costumbrista writing that captured local speech, social types, and the changing life of Argentina at the turn of the century.

His books often drew on direct experience and careful observation. Works such as Memorias de un vigilante and Viaje al país de los matreros show his interest in police life, popular culture, and the rougher edges of urban and rural society, all told with wit and an eye for memorable detail.

He died in Buenos Aires in 1903, just before turning 45. Even so, his work left a lasting mark: readers remember him for bringing ordinary people, street life, and Argentine customs onto the page in a voice that feels both documentary and entertaining.