A protagonist of the 1910 Mexican revolution, General Maytorena (1867-1948) was governor of Sonora, a province of northern Mexico, and an ardent supporter of the short-lived presidency of Francisco Madero. Caught in the internecine conflict between the revolutionaries following Madero's overthrow and assassination, he fled to exile in Los Angeles. He provided an account of his role in Sonora and the revolution in Mi Gobieno en Sonora, one of the manuscripts found in his papers along with correspondence, photographs, newspaper clippings and documents - a collection of at least 2,272 pieces contained in over 4000 pages covering the years 1908 to 1946. The collection contains significant items from Maytorena's correspondence with Venustiano Carranza, a conservative landowner and politician who nonetheless worked to coordinate the various revolutionary forces; Francisco Madero, the overthrown president; Alvaro Obregon, a notable revolutionary field commander in Sonora; Victoriano Huerta, a professional soldier loyal to former president Diaz, who engineered the coup against Madero; the Chihuahauan guerilla leader Francisco "Pancho" Villa, and other revolution participants.