When the pope saw Liutprand march southward with the exarch he must have known that the whole of the future depended upon the outcome of this act. Liutprand presently encamped with his army in the plain of Nero between the Vatican and Monte Mario. There the pope met him and, even as Leo the Great had done upon the banks of the Mincio, and as Gregory the Great had done upon the steps of S. Peter’s, overawed the barbarian. Liutprand laid his crown and his sword at the pope’s feet and begged, not only for his own forgiveness, but for that of the exarch his ally. The moment of enormous danger passed, the pope received both his enemies; but from that moment it was evident that the Lombards were not to be trusted and must one day feel the weight of the papal arm.
Gregory died in February 731, and was succeeded by Gregory III. who continued his predecessor’s Italian policy. The great and terrible danger which had suddenly threatened the whole of papal policy when Liutprand and the exarch approached one another seems to have haunted the third Gregory. His obvious defence was to support the dukes against Liutprand, and this he did. Liutprand marched down against him and seized several towns in the duchy of Rome. It is now that the future begins to declare itself. The pope in his peril, a peril that would presently increase, made an appeal to the great Christian champion, Charles Martel; he appealed to the Franks; in the event, as we know, it was the Franks who saved the situation. In 740, however, Charles Martel refused to interfere; he was the kinsman of Liutprand and his son was a guest at the court of Pavia; that son was to be king Pepin the Deliverer—the father of Charlemagne, the first emperor of the restored West.
That appeal for help was in all probability not made only on account of the threat of Liutprand against Rome. It was obvious and more and more obvious that the imperial power in Italy was about to dissolve. What was to take its place? The papacy? Yes, but the state of Italy, the hostility of Liutprand, the whole attitude and condition of the Lombards, forced upon the papacy the necessity of finding a champion, a soldier and an army. That champion Gregory hoped to find in Charles Martel; his successors found him in Charles’s son Pepin and in Charlemagne.
I say the appeal of the pope for help was not made only on account of the Lombard threat against Rome. It was the sudden dissolution of the imperial power that called it forth. In or about 737, the city of Ravenna, as we may believe, was besieged and taken by Liutprand and for some three years remained in his hands, till at the united prayers of exarch and pope the Venetians fitted out a fleet and recaptured it for the empire as we may think in 740.
[Footnote 1: I follow Hodgkin, vi. p. 482 et seq., and Appendix F. Cf. also for discussion as to the date, Pinton in Archivio Veneto (1889), pp. 368-384, and Monticolo in Archivio della R. S. Romana di St. Pat. (1892), pp. 321-365.]