Pope Stephen III
Pope Stephen II crossed the Alps to appeal for the aid of Pepin the Short upon his election in 752, following the Lombard conquest of Ravenna, resulting in the Donation of Pepin which strengthened the claim of the Popes to the "de facto" Papal States, and thus the incentives for secular interference in Papal selection. The death of Stephen II's brother and successor Pope Paul I was followed by a bloody schism characterized by Toto of Nepi and Pope Stephen III; after Toto had his eyes gouged out and was imprisoned, Stephen III decreed that the entire Roman clergy had the right to elect the Pope but restricted eligibility for election to the cardinal-priests and cardinal-deacons (incidentally, the first use of the term "cardinals" to refer to the priests of the titular churches or the 7 deacons); the cardinal-bishops, supporters of Toto, were excluded. Of course, the Roman laity rapidly regained its role after Stephen III's decree, and maintained its participation until 1059.