House of Farnese
Gradoli's origins date to the Middle Ages, when a castle was built here: this could be reached only through a series of steps (in Latin, "gradus"), whence its name. Matilde of Canossa donated the castle to the Papal States in the 11th century. In the following century the town became a free commune, but was soon conquered by Orvieto. Revolts followed, which were violently suppressed. In the 15th century Gradoli became a possession of the House of Farnese, who established here a summer residence under Pope Paul III. Gradoli, part of the Duchy of Castro, returned to the Papal States after the latter was crushed in the War of Castro (1649). It became part of the newly formed Kingdom of Italy in 1871.