Then occurred a very important scene. On Christmas Day, in the year 800, as Charles was rising from prayer in the Church of St. Peter, the Pope, who had everything in readiness, clapped a crown upon his head and hailed him Cæsar and Augustus. There was great popular applause. But Eginhard, the friend and biographer of Charlemagne, says that the new emperor was by no means pleased by this coup of Pope Leo's. If he had known this was to happen, he said, "he would not have entered the church, great festival though it was." No doubt he had been thinking and talking of making himself emperor, but he had evidently not intended that the Pope should make him emperor. He had had some idea of marrying the Empress Irene, who at that time reigned in Constantinople, and so becoming monarch of both Eastern and Western Empires. He was now obliged to accept the title in the manner that Leo III had adopted as a gift from the Pope, and in a way that estranged Constantinople and secured the separation of Rome from the Byzantine Church.
At first Byzantium was unwilling to recognize the imperial title of Charlemagne. But in 810 a great disaster fell upon the Byzantine Empire. The pagan Bulgarians, under their Prince Krum (802-814), defeated and destroyed the armies of the Emperor Nicephorus, whose skull became a drinking-cup for Krum. The greater part of the Balkan peninsula was conquered by these people. (The Bulgarian and the English nations thus became established as political unities almost simultaneously.) After this misfortune Byzantium was in no position to dispute this revival of the empire in the West, and in 812 Charlemagne was formally recognized by Byzantine envoys as Emperor and Augustus.
So the Empire of Rome, which had died at the hands of Odoacer in 476, rose again in 800 as the "Holy Roman Empire." While its physical strength lay north of the Alps, the centre of its idea was Rome. It was therefore from the beginning a divided thing of uncertain power, a claim and an argument rather than a necessary reality. The German sword was always clattering over the Alps into Italy, and missions and legates toiling over in the reverse direction. But the Germans could never hold Italy permanently, because they could not stand the malaria that the ruined, neglected,
