When Pepin, his own ambition satisfied, turned his attention to the Pope’s affairs, the Lombards had just succeeded in over-running the Exarchate of Ravenna, the seat of the imperial government in Italy. Collecting an army, the King of the Franks crossed the Alps without encountering any opposition, marched on Pavia, the Lombard capital, and struck such terror into his enemies that, almost without fighting, they agreed to the terms that he dictated.
Legally, he should have at once commanded the restoration of the Exarchate to the Empire, but there was no particular reason why Pepin should gratify Constantinople, while he had a very strong inclination to please Rome. He therefore told the Lombards to give the Exarchate to Stephen II, who was Pope at that time, and this they faithfully promised to do; but, as he turned homewards, they began instead to oppress the country round Rome, preventing food from entering the city and pillaging churches.
[Sidenote: The Temporal Power of the Papacy]
Pepin was very angry when he heard the news. Once more he descended on Italy, and this time the Lombards were compelled to keep their word, and the Papacy received the first of its temporal possessions, ratified by a formal treaty that declared the exact extent of the territory and the Papal rights over it. This was an important event in mediaeval history, for it meant that henceforward the Pope, who claimed to be the spiritual head of Christendom, would be also an Italian prince with recognized lands and revenues, and therefore with private ambitions concerning these. It would be his instinct to distrust any other ruler in the peninsula who might become powerful enough to deprive him of these lands; while he would always be faced, when in difficulties, by the temptation to use his spiritual power to further purely worldly ends. On the way in which Popes dealt with this problem of their temporal and spiritual power, much of the future history of Europe was to depend.
Pepin, in spite of his shrewdness, had no idea of the troubles he had sown by his donation. Well pleased with the generosity he had found so easy, with the title of ‘Patrician’ bestowed on him by the Pope, and perhaps still more by the spoils that he and his Franks had collected in Lombardy, he left Italy, and was soon engaged in other campaigns nearer home against the Saracens and rebellious German tribes. In these he continued until his death in 768.