Historians have debated for centuries whether Charlemagne was aware of the Pope's intent to crown him Emperor prior to the coronation(Charlemagne declared that he would not have entered Saint Peter's had he known), but that debate has often obscured the more significant question of
why the Pope granted the title and why Charlemagne chose to accept it once he did.
Roger Collins points out (
Charlemagne, pg. 147) "that the motivation behind the acceptance of the imperial title was a romantic and antiquarian interest in reviving the Roman empire is highly unlikely." For one thing, such romance would not have appealed either to Franks or Roman Catholics at the turn of the ninth century, both of whom viewed the
Classical heritage of the Roman Empire with distrust. The Franks took pride in having "fought against and thrown from their shoulders the heavy yoke of the Romans" and "from the knowledge gained in baptism, clothed in gold and precious stones the bodies of the holy martyrs whom the Romans had killed by fire, by the sword and by wild animals", as Pippin III described it in a law of 763 or 764 (Collins 151). Furthermore, the new title — carrying with it the risk that the new emperor would "make drastic changes to the traditional styles and procedures of government" or "concentrate his attentions on Italy or on Mediterranean concerns more generally" (Collins 149) — risked alienating the Frankish leadership.
For both the Pope and Charlemagne, the Roman Empire remained a significant power in European politics at this time, and continued to hold a substantial portion of Italy, with borders not very far south of the city of Rome itself — this is the empire historiography has labelled the Byzantine Empire, for its capital was Constantinople (ancient Byzantium) and its people and rulers were
Greek; it was a thoroughly Hellenic state. Indeed, Charlemagne was usurping the prerogatives of the Roman Emperor in Constantinople simply by sitting in judgement over the Pope in the first place:
:
By whom, however, could he [the Pope]
be tried? Who, in other words, was qualified to pass judgement on the Vicar of Christ? In normal circumstances the only conceivable answer to that question would have been the Emperor at Constantinople; but the imperial throne was at this moment occupied by Irene. That the Empress was notorious for having blinded and murdered her own son was, in the minds of both Leo and Charles, almost immaterial: it was enough that she was a woman. The female sex was known to be incapable of governing, and by the old Salic tradition was debarred from doing so. As far as Western Europe was concerned, the Throne of the Emperors was vacant: Irene's claim to it was merely an additional proof, if any were needed, of the degradation into which the so-called Roman Empire had fallen. (
John Julius Norwich, Byzantium: The Early Centuries, pg. 378)
For the Pope, then, there was "no living Emperor at the that time" (Norwich 379), though
Henri Pirenne (
Mohammed and Charlemagne, pg. 234n) disputes this saying that the coronation "was not in any sense explained by the fact that at this moment a woman was reigning in Constantinople." Nonetheless, the Pope took the extraordinary step of creating one. The papacy had since 727 been in conflict with Irene's predecessors in Constantinople over a number of issues, chiefly the continued Byzantine adherence to the doctrine of iconoclasm, the destruction of Christian images; while from 750, the secular power of the Byzantine Empire in central Italy had been nullified. By bestowing the Imperial crown upon Charlemagne, the Pope arrogated to himself "the right to appoint ... the Emperor of the Romans, ... establishing the imperial crown as his own personal gift but simultaneously granting himself implicit superiority over the Emperor whom he had created." And "because the Byzantines had proved so unsatisfactory from every point of view—political, military and doctrinal—he would select a westerner: the one man who by his wisdom and statesmanship and the vastness of his dominions ... stood out head and shoulders above his contemporaries."
With Charlemagne's coronation, therefore, "the Roman Empire remained, so far as either of them [Charlemagne and Leo] were concerned, one and indivisible, with Charles as its Emperor", though there can have been "little doubt that the coronation, with all that it implied, would be furiously contested in Constantinople." (Norwich,
Byzantium: The Apogee, pg. 3) How realistic either Charlemagne or the Pope felt it to be that the people of Constantinople would ever accept the King of the Franks as their Emperor, we cannot know; Alcuin speaks hopefully in his letters of an
Imperium Christianum ("Christian Empire"), wherein, "just as the inhabitants of the [Roman Empire] had been united by a common Roman citizenship", presumably this new empire would be united by a common Christian faith (Collins 151), certainly this is the view of Pirenne when he says "Charles was the Emperor of the
ecclesia as the Pope conceived it, of the Roman Church, regarded as the universal Church" (Pirenne 233).
What we
do know, from the Byzantine chronicler
Theophanes (Collins 153), is that Charlemagne's reaction to his coronation was to take the initial steps toward securing the Constantinopolitan throne by sending envoys of marriage to Irene, and that Irene reacted somewhat favorably to them. Only when the people of Constantinople reacted to Irene's failure to immediately rebuff the proposal by deposing her and replacing her with one of her ministers, Nicephorus I, did Charlemagne drop any ambitions toward the Byzantine throne and begin minimising his new Imperial title, and instead return to describing himself primarily as
rex Francorum et Langobardum.
The title of emperor remained in his family for years to come, however, as brothers fought over who had the supremacy in the Frankish state. The papacy itself never forgot the title nor abandoned the right to bestow it. When the family of Charles ceased to produce worthy heirs, the pope gladly crowned whichever Italian magnate could best protect him from his local enemies. This devolution led, as could have been expected, to the dormancy of the title for almost forty years (924-962). Finally, in 962, in a radically different Europe from Charlemagne's, a new Roman Emperor was crowned in Rome by a grateful pope. This emperor,
Otto the Great, brought the title into the hands the kings of Germany for almost a millennium, for it was to become the Holy Roman Empire, a true imperial successor to Charles, if not
Augustus.