So he proceeded on December 23d to exculpate himself by formally declaring his innocence before a great assembly of secular and ecclesiastical dignitaries, expressly mentioning that the proceeding was voluntary and not required by the canons of the Church. In this way the immediate cause of the expedition of the Franks was disposed of, but Charles remained in Rome in order to provide for things needful in the administration of his Italian dominions.
On Christmas Day a multitude had gathered together to celebrate the festival. As the King rose from prayer at the Confession of St. Peter the Pope placed the imperial diadem upon his head. The congregation, acting under one inspiration, joined spontaneously in the acclamation, used in former days in Rome, and still customary at the time at Constantinople,—“Life and Victory to Charles the Pius Augustus, crowned by God, the great and peace-bringing Emperor.”
Three times the formula was repeated. After this proclamation the Pope reverenced the new Emperor, genuflecting, as was the Roman custom, and probably this act of homage was repeated by all who were present. On the same day the Emperor’s son, Karl, was anointed King by the Pope, just as his brothers, Pippin and Louis, had been elevated to the royal dignity twenty years before. A few days later the Emperor, sitting as supreme judge, condemned to death the Pope’s accusers, sentences which, at Leo’s request, were mitigated to deportation.
The biographer of Charles represents the ceremony of the coronation as a surprise, prepared by the Pope without consulting Charles, and so done not only without his will, but contrary to his desire. The Emperor, indeed, is reported to have said that, if he had known of the Pope’s intention, he would not have visited the Basilica. These words may be interpreted as an expression of the usual formula of humility, frequent in ecclesiastical elections on the part of the successful candidate, or else they may mean that the Emperor objected to the way in which the dignity was bestowed. It will be noted that the act of placing the crown on his head preceded the acclamation of the people’s choice. The details of the ceremonial were copied from the one used at Constantinople, where it had long been the custom for the Emperor to be crowned by the Patriarch. But, according to the political theory of the time, the imperial dignity was not conferred by the receiving of the diadem, but by the election of the Roman people and army, and by the formal act of homage done at the time. The Pope, by his presence, added more solemnity to the occasion, but his intervention added nothing in the way of legal validity to it.
Charles’ own point of view is shown plainly enough in the fact that in 813 he proclaimed his son Louis Emperor and crowned him with his own hands. As he acted here without requesting the coöperation of the Pope, a purely lay method of conferring the imperial dignity may have appealed better to his convictions than that followed in his own case. But there could have been no improvised procedure in the ceremony at St. Peter’s. Charles could not have been made Emperor against his will, nor is it possible to harmonize the details of the ceremony with such an explanation. How could the coronation have been an impulsive act on the Pope’s part, taken without the Emperor’s knowledge, when the diadem was in readiness, and the great congregation were prepared to repeat without confusion the words of acclamation? Such preparations must have had the consent of the Frankish ruler, for it is most unlikely that he should not have known of them. His own objections, therefore, were probably due to certain features of the ceremony actually carried out, those, namely, by which the Pope took the initiative. A stricter following of ancient precedent, at a time when no ceremonial change should have been introduced by which the legitimacy of the succession could be questioned, would have approved itself to Charles. An emperor had to be provided for the West, and scrupulosity in following precedents was desirable, especially in view of the doubt as to whether the Empress Irene could, as a woman, legally hold supreme power at Constantinople.
It must be remembered that there had been several attempts made in the seventh and eighth centuries to revive the connection between Rome and the imperial dignity. But they had failed because there was no considerable and acknowledged political force behind them. Now, under the extensive rule of the Frankish King, the elements required to give an actual validity to the imperial claim were present in an overwhelming degree. Charles was in control of most of the territory once belonging to the empire in Western Europe, and along the Eastern and Southeastern frontiers he had succeeded in extending its limits—a task unparalleled by the achievements in these same regions of the greatest of the Roman Emperors. The Teutonic peoples, who centuries before had made their first appearance as “fœderati,” in the service of the Empire, were now component parts of it, and had definitely entered the sphere of Roman civilization. What Athaulf had deemed to be impossible, what neither Odoacer, Theodoric, nor the Lombard Kings had tried or dared to do, Charles had done, now that, advancing from the title of Patrician, which had been held often by the barbarian rulers, he claimed for the Germans the full right to the imperial name.
In its ecclesiastical relations the revived Empire differed from the old. The Pope had become a factor in the political evolution of the West in a way unknown to the age of Athaulf, Theodoric, or Odoacer. Gregory the Great had turned to the East as a subject of the Roman Empire, to ask aid of his legitimate Emperor; the bishops of Rome, in the eighth century, as equals, turned to the Franks, and of this alliance the ceremony of Christmas Day, 800, was the logical sequence.
For the Germanic peoples the coronation of Charles did not mean absorption into a unified system of absolutism, such as prevailed in the East; but it did mean that the predominant factor in their future was to be their relation in the logical sense to the Italian peninsula, and it is just this relationship in its various phases which was worked out in the Middle Ages, and so it may justly be called the distinguishing mark of the medieval period.
Charles’ assumption of the imperial title did not imply that he ceased to regard himself as the head of a Germanic people, nor was there manifest on his part any intention to shift the existing Teutonic basis of his rule towards a Latin center. For several months after the coronation ceremony he remained in Italy, but the Alps were recrossed in the summer of 801, and during the rest of his life he never again set foot on Italian soil.
With the Eastern Empire, which might have been stirred to active hostility by the introduction of a rival claimant to the imperial throne, relations continued to be good. Embassies passed from one court to another, and it is reported by a Greek chronicler that Charles transmitted officially to the Empress Irene a proposal that the two empires should be united by their marriage. In 803 the Empress Irene died, after her deposition had been brought about by a palace revolution by which Nicephorus, the Grand Treasurer, was placed on the throne. In 806, for a short time, these peaceful relations were broken by a contention over the possession of Venice, whose commercial importance was beginning to be recognized. A Byzantine fleet appeared off the lagunes, but was unable to prevent the coveted islands from being taken by Pippin, Charles’ representative in Italy, who brought the contest to a close in 810 by a combined attack on sea and land. In 812, as a compensation for acknowledging Charles as Roman Emperor, the Adriatic territories, Venetia, Istria, Liburnia, and Dalmatia, were restored to Byzantine rule.