The Franks: 753-772
In 753 the pope, Stephen II, ask to the Franks king Pepin III, to help him against the Lombards who have recently taken the city of Ravenna and who pose a similar threat to Rome. The pope meet Pepin at the abbey of St Denis, near Paris, together with his two young sons Charles and Carloman. Pepin invades northern Italy in 754, and again in 756.
He can drive the Lombards from Ravenna. But he does not restore the Byzantine emperor. Instead, he hands over large areas of central Italy to the pope .
The land given to pope Stephen in 756, gives the papacy the role of a temporal power.
These lands, increased and reduced at various periods of history, are the papal states over which the popes continue to rule until 1870 when Italian king Emanuel III of Savoy conquered Rome.
In the short term the temporal rule of the popes is shaky. After a few years the Lombards again invade their territory and the new pope Adrian I appeals for help to the new Frankish king Charlemagne. This time the Lombard threat is conclusively resolved and northern Italy, is reduced to an appendix of France and Germany , within the Frankish empire .