After the Lombard conquest the imperial dominion in Italy were administered by a governor, called the Exarch, who dwelt at Ravenna, the northernmost and strongest of the imperial fortresses. All the Italian provinces were nominally beneath his control, but, as a matter of fact, he was only treated with implicit obedience by those of his subordinates who dwelt in his own neighbourhood. He found it harder to enforce his orders at Naples and Reggio, or in the distant islands of Sicily and Sardinia. But it was the bishops of Rome who profited most by his absence: although a “duke”, a military officer of some importance, dwelt at Rome, he was from the first over shadowed by his spiritual neighbour. Even during the days of the Ostrogoths the Roman bishops had acquired considerable importance, as being the chief official representatives of the Italians in dealings with their Teutonic masters. But they spoke with much more freedom and weight when they had to do, not with a King of Italy dwelling quite near them, but with a mere governor fettered by orders from distant Constantinople.
Pope Gregory the Great
Gregory the Great [590-604] was the first of the popes who began to assume an independent attitude and to treat the Exarch at Ravenna with scant ceremony. He was an able and energetic man, who could not bear to see Rome suffering for want of a ruler on the spot, and readily took upon himself civil functions, in spite of the protests of his nominal superior the Exarch. In 592, for example, he made a private truce for Rome with the Lombard Duke of Spoleto, though the latter was at war with the empire.
The Emperor Maurice stormed at him as foolish and disobedient, but did not venture to depose him, being too much troubled with Persian and Avaric wars to send troops against Rome. On another occasion Gregory nominated a governor for Naples, instead of leaving the appointment to the Exarch. In 599 he acted as mediator between the Lombard king and the government at Ravenna, as if he had been a neutral and independent sovereign. Although he showed no wish to sever his connection with the Roman Empire, Gregory behaved as if he considered the emperor his suzerain rather than his immediate ruler. He would never give in on disputed points, issued orders which contradicted imperial rescripts, and maintained a bitter quarrel with successive patriarchs of Constantinople, who possessed the favour of Maurice. When the patriarch John the Faster took the title of “oecumenical bishop”, Gregory wrote to Maurice to tell him that the presumption of John was a sure sign that the days of Antichrist were at hand, and to urge him to repress such pretensions by the force of the civil arm. This is one of the first signs of the approach of that mediaeval view of the papacy which imagined that it was the pontiff’s duty to censure and advise kings and emperors on all possible topics and occasions.
Gregory’s immediate successors were not men of mark, or a breach with the empire might have been precipitated. The final disavowal of the supremacy of the Constantinopolitan monarch was to be still delayed for nearly two hundred years. The wars between the Exarchs of Ravenna and the Lombard kings were little influenced by interference from the East. The emperors during the last thirty years of the sixth century were far more engrossed with their Persian and Slavonic wars. Contests with the Great king of the East occupied no less than twenty years in the reigns of Justin II., Tiberius, and Maurice. War was declared in 572, and did not cease till 592. Like the struggle between Justinian and Chosroes I., thirty years before, it was wholly indecisive.
There were more plundering raids than battles, and the frontier provinces of each empire were reduced to a dreadful state of desolation and depopulation: if the Persians pushed their ravages as far as the gates of Antioch, Roman generals penetrated deep into Media and Corduene, where the imperial banner had not been seen for two hundred years. The net result of the whole twenty years of strife was that each combatant had seriously weakened and distressed his rival, without obtaining any definite superiority over him. Forced to make peace by the pressure of a civil war, Chosroes II gave back to Maurice the two frontier cities of Dara and Martyropolis, the sole trophies of twenty campaigns, and ceded him a slice of Armenian territory. But these trivial gains were far from compensating the empire for the fearful losses caused by dozens of Persian invasions.
(Source: “The Byzantine Empire”, by C. W. C. Oman)
Roman Emperor Maurice
Research-Selection for NovoScriptorium: Anastasius Philoponus