But all Italy regarded Martin as a martyr to orthodoxy, and his fate did much to estrange the Romans from their loyalty to the empire. Nor was their wrath diminished by the sacrilegious plunder of the Pantheon and other Roman churches, which Constantinus carried out, when in 663 he deigned to visit his Western dominions. It would seem that Constantinus himself was fully conscious that the Roman see was growing too strong, and deliberately strove to sap its resources, for at this time he granted to the archbishop of Ravenna a formal exemption from any duty of spiritual obedience to the Pope as patriarch of the West, and constituted him an independent authority in the exarchate. For twenty years this schism of Rome and Ravenna continued, but in the end the old traditional prestige of the see of St. Peter triumphed over the ambition of the Ravennese archbishops. If there had been a strong pontiff at this moment, it is probable that an open rupture might have taken place between the papacy and the empire. But pope Vitalian was a weak man, the fate of his predecessor Martin had cowed him, and the idea of cutting Rome away from the _respublica Romana_, as the empire was still habitually called, had not yet entered into the minds of the Italian subjects of Byzantium. To disown the Imperial supremacy would have been tantamount to throwing Rome into the hands of king Grimoald the Lombard, and neither Pope nor people contemplated such a prospect with equanimity. Accordingly the breach between Rome and Byzantium was deferred for another generation. After Constantinus was dead, more friendly relations reigned for a space, for his son Constantine V. was impeccably orthodox. He held the Council of Constantinople in 681 with the high approval of pope Agatho, whose representatives duly appeared at it, to join in the final crushing of the Monothelite heretics. Constantine, in the fulness of his friendship to the papacy, even granted to the Roman see the dangerous privilege that when at papal elections the suffrages of the clergy, the people, and the soldiery,—the garrison of Rome—were unanimously fixed on any one person, that individual might be at once consecrated bishop of Rome, without having to wait for an imperial mandate of approval from Constantinople. As a matter of fact, however, unanimous elections were very rare, and the exarchs of Ravenna are still found interfering to decide between the claims of rival candidates.