Given the proximity of Petriolo to the ancient Roman city Urbs Salvia (Urbisaglia, in the current Italian language, just 5 km far from Petriolo), it is believed that an influential citizen, a civilian or a soldier, decided to build his estate, a Praetolium, in the village which will be named Petriolo.
It is assumed that the ancient Castle has been built on its ruins by the Benedictine monks, close to the Abbot Farfa. Documents dating from the year 1000 state that the current territory of Petriolo belonged to the Bishop of the city of Fermo. He received it as a gift by a certain Butto or Buttolo, who had bought it, or more probably, usurped it to the Benedictine monks, skilled landowners, but torn by internal discord.
Then, in 1070, the Bishop of Fermo sold the Castle (together with part of its properties) to a local lord, Grimaldo. He’s Attone’s son, member of the noble family Della Marca. We owe the foundation of Petriolo Castle to him.
In 1264, Manfred, King of Sicily, annoyed with the treason made by Gentile De Nobili’s sons, who refused to remain in the Ghibelline faction, ordered the destruction of the Castle. The other punishment was supposed to be the deportation of the inhabitants to the nearby Montolmo, but, for unknown reasons, this didn’t happen.
