Disappearing from history under the Roman domination, it is again known in 862 when a county was founded by Emperor Louis II, under the Aldobrandeschi suzerainty. The Aldobrandeschi were the most powerful feudataries of southern Tuscany for more than four centuries, disappearing in 1312 when Margherita, son of Ildibrandino, died without male heirs. His daughter Adelaide married to Romano di Gentile Orsini, who added the city to the family fiefs.