The declaration that the bishops were forced to sign upon their consecration by the pope by no means settled matters.  In 648 this declaration itself was in dispute as to its interpretation, for Constans II. had conferred upon the See of Ravenna the privilege of autonomy, and at this time the bishop did not go to Rome for consecration.  The Iconoclastic heresy of Constantinople, however, indirectly brought about peace between the pope and his suffragan, for Ravenna was in this whole heartedly Roman.

It was then, by means of an instrument still very uncertain, that the papacy was forced to govern its new state, and in these circumstances, friendly relationship with Constantinople daily becoming more impossible, it is not surprising that we see the pope making an attempt to come to some sort of permanent reconciliation with Desiderius; and indeed when pope Paul died in 767 undoubtedly a peace had been arranged.

All might have been well if pope Paul’s successor had been regularly chosen; but a layman Constantine was elected by a rabble at the instigation of his brother Toto of Nepi.  Christopher and his son Sergius, who held two of the greatest offices in the papal chancery, decided to call in the aid of the duke of Spoleto to attack Constantine, Rome was entered, and in the appalling confusion the Lombards elected a certain priest named Philip to be pope.  Christopher appeared, Philip was turned out, and Stephen III., a Sicilian, was regularly chosen.  That was in 768, and in the same year king Pepin died and was succeeded by his two sons, Charles to whom apparently fell Austrasia and Neustria, and Carloman who took Burgundy, Provence, and Swabia.

The death of Pepin left the papacy without a champion.  Nor was this all, as soon appeared.  Charles and Carloman began to quarrel and to effect their reconciliation, or to avert its consequences, Bertrada, their mother, counselled and succeeded in forcing upon them a friendship and an alliance with the Lombards which meant the complete abandonment of Italy upon the part of the Franks.  This alliance was to be secured by a double marriage.  Charles was to marry Desiderata, the daughter of the Lombard king, while Gisila, Bertrada’s daughter, was to marry Desiderius’ heir.  It is obvious that S. Peter was in peril, nor was pope Stephen slow to denounce the whole arrangement.  His remonstrance, however, was ineffectual and there remained to him but one thing to do:  to arrange himself with the now uncurbed Lombard king.  This was exceedingly difficult, because his own election had been achieved only by the humiliation of the Lombards.  However, he managed it at the price of civil war.  Desiderius and his army entered Rome at the behest of the pope, who celebrated Mass before the king in S. Peter’s.  The Franks were checkmated.