From 756 to 857, the papacy shifted from the influence of the Byzantine Empire to that of the kings of the Franks. Pepin the Short (ruled 751โ768), Charlemagne (r. 768โ814) (co-ruler with his brother Carloman I until 771), and Louis the Pious (r. 814โ840) had considerable influence in the selection and administration of popes. The "Donation of Pepin" (756) ratified a new period of papal rule in central Italy, which became known as the Papal States.
This shift was initiated by the Lombards conquering the Exarchate of Ravenna from the Byzantines, strengthened by the Frankish triumph over the Lombards, and ended by the fragmentation of the Frankish Kingdom into West Francia, Middle Francia, and East Francia. Lothair I continued to rule Middle Francia which included much of the Italian peninsula, from 843 to 855.
This period was "a critical time in Rome's transformation from ancient capital to powerful bishopric to new state capital."[1] The period was characterized by "battles between Franks, Lombards and Romans for control of the Italian peninsula and of supreme authority within Christendom."[2]