While Charles was at Rome there was converse between him and the pope concerning the Duke of Bavaria. Tassilo had been a liberal friend to the Church, and had successfully prosecuted the enterprise of the conversion of the Sclaves on his eastern frontier. Hadrian well knew how strained were the relations between duke and king, and was, we may believe, sincerely anxious to reconcile Tassilo to his mighty cousin. A joint embassy was despatched to the Bavarian court: the pope being represented by the bishops, Damasus and Formosus, the king by the deacon Richulf and Eberhard the arch-cupbearer. “And when,” says the chronicler, “these emissaries, obedient to their instruction, had conversed with the aforesaid duke, and reminded him of his old oaths to King Pippin, King Charles and the Franks, his heart was so much softened that he declared his willingness to hasten at once to the king’s presence, if such hostages were given him as to remove all doubt of his personal safety. These having been given, he came without delay to the king at Worms, swore the oath which was dictated to him, and gave twelve chosen hostages for the fulfilment of his promise that he would keep as towards King Charles and his loyal subjects all the oaths which he had sworn aforetime to King Pippin. These hostages were promptly brought to the king in his villa of Quierzy by Sindbert, Bishop of Ratisbon. But the said duke returning home did not long remain in the faith which he had promised.” Notwithstanding the ominous words with which the chronicler concludes, a great moral victory had certainly been gained by Charles, and the attitude of sullen semi-independence which Tassilo had maintained for nearly twenty years was now abandoned. For six years (781–787) the name of Tassilo disappears from the chronicles, and we may conclude that he was for so long a fairly loyal subject of the Frankish kingdom, or rather perhaps that he committed no such open act of rebellion as to compel Charles, engrossed as he was during these years by the war with Widukind, to send any of his sorely needed Frankish warriors for the chastisement of his Bavarian vassal.