were in the western part of the Byzantine Empire three themes under patrician governors — the Exarchate, Rome, and Sicily (with Calabria), of which the latter was for the most part Greek in language and culture, whereas the two first were Latin.
After the disappearance of the patrician governor from Rome, the pope took his place and claimed the right to rule directly the city of Rome with her surroundings, and also indirectly the ducatus attached to Rome in the north and south as supreme lord of the two duces, and to restore more or less the situation which had existed during the Italian revolt. The papal bureaucracy, which had been developed to a certain extent on the model of the Byzantine bureaucracy, took the place of the imperial administration. In other words, the pope assumed the dicio over Rome and the district belonging to it. Here in times of war and peace he reigned like the exarch before him, negotiated and concluded truces with the Lombards, recognising however the suzerainty of the emperor, whose commands he received through special embassies, and reckoning his dates from the years of the emperor's reign. At the emperor's command he went to King Aistulf at Pavia, and thence — probably also in accordance with the imperial wishes — crossed the Alps and visited the king of the Franks. The concessions of Pepin and Charles the Great were called "restitutions," by which was understood that the old boundaries between the Empire and the Lombard kingdom, as they had been recognised before Liutprand's reign, were restored, and the sovereignty of the emperor within these boundaries was legally undisputed. This is proved by the fact that down to the year 781 the popes reckoned their dates from the years of the emperor's reign. The dispute between the popes and the Frankish kings on the one side and the emperors on the other arose from the fact that Pepin gave the dicio of the restored domains to the pope, and not to the emperor who laid claim to it, so that the pope became the real master in the new Pontifical State and no room was left for a representative of the emperor. Moreover the pope overstepped the limits which had hitherto bounded the sphere of his power, by including in his dicio not only the former patrician ducatus of Rome but also the exarchate proper. This gave rise to protracted struggles with the archbishop of Ravenna, who as the exarch's successor assumed the dicio north of the Apennines. It was probably in the year 781 that the new state of affairs was officially recognised and thereby consolidated, by an agreement between Charles and Pope Hadrian on the one side, and the Greek ambassador on the other. According to this agreement the emperor, or rather the empress-regent Irene, abandoned all claims to the sovereignty over the Pontifical State in favour of the pope.
The emancipation from the dicio of the imperial government of those parts of Italy which still remained under Byzantine rule, was carried out in a way analogous to that of the Pontifical State, the only difference
