The boundless promises and awful denunciations of the pope might have been alike unavailing, had not other and stronger motives inclined the king to make a second expedition into Italy. The interests of his dynasty were so closely connected with those of the Roman church, that he could not desert the pope in this imminent peril without weakening the foundations of his throne; and his honour as a warrior and a king seemed to require that the Lombards should be punished for their breach of faith. The influence of Boniface, too (who was still alive, though he died before the end of the campaign), was no doubt exerted in behalf of the papacy which he had done so much to raise. Pepin determined to save the pope, but he did so at the imminent risk of causing a revolt among his own vassals, who openly and loudly expressed their disapproval of the war. “This war” (against the Lombards), says Einhard,
Pepin found means to pacify or overawe these turbulent dissentients, and persisted in his determination again to save the head of the church from his enemies.
In this second Italian expedition Pepin was accompanied by his nephew Tassilo, who, in obedience to the war-ban of his liege lord, joined him with the Bavarian troops. The Frankish army marched through Châlons and Geneva to the same valley of Maurienne and to the passes of Mont Cenis, which, as in the former year, were occupied by the troops of Aistulf. The Franks, however, in spite of all resistance, made their way into Italy, and took a fearful vengeance for the broken treaty, destroying and burning everything within their reach, and giving no quarter to their perfidious enemies. They then closely invested Pavia; and Aistulf, convinced of his utter inability to cope with Pepin, again employed the willing services of the Frankish seigneurs to negotiate a peace. Pepin on his side accepted the overtures made to him with singular facility, but obliged Aistulf to give fresh hostages, to renew his oaths, and, what was more to the purpose, to deliver up a third of the royal treasure in the city of Pavia.[131] Aistulf also agreed to renew an annual tribute, which is said to have been paid for a long time previously to the Frankish monarchs.
And thus a second time was the papacy delivered from a danger which went nigh to nip its budding greatness, and reduce it to the rank of a Lombard bishopric.
Aistulf died while hunting in a forest (probably in December, 756) before he had had time to forget the rough lessons he had received and to recover from his losses in blood and treasure.
A danger from another quarter, which threatened the development of the papal power, was also warded off by the power and steadfastness of Pepin. When the exarchate of Ravenna was overrun by the Lombards, it was taken, not from the pope, but from the Greek emperor; and even the towns and territories which were virtually under the sway of the papal chair, were, nominally at least, portions of the Eastern Roman Empire. As Stephen had never formally renounced his allegiance to the emperor, he could receive even the Roman duchy only as a representative of his sovereign, and to the other remains of the Roman Empire in Italy he had no claim whatever. The Lombards had dispossessed the Greeks, and the Franks had expelled the Lombards. It was therefore open to the conqueror to bestow his new acquisition where he pleased; but, at all events, the claim of the Greek emperor was stronger than that of his vassal the bishop of Rome. We cannot wonder, then, when we read that ambassadors from Constantinople came to meet Pepin in the neighbourhood of Pavia, and begged him to restore Ravenna and the other towns of the exarchate to the Roman emperor. “But they did not succeed,” says the chronicler,