Stephen now was at the mercy of Desiderius, who used every means in his power to compel him to surrender voluntarily to him the possessions which Pepin had restored to the Church. This proved a fresh source of resentment on Charlemagne’s part against Desiderius. He only waited for Stephen to appeal to him for help, and held himself in readiness to lend it; but his plans were frustrated by a new move which he could not resist. His mother, who had gone to Italy, interposed and wrote letters to him which led to anything rather than a warlike view of the situation. Although she had no doubt of the lion-hearted nature of her son, or of the valor of his army, she could not view the dangers arising from a conflict between the Franks and the Lombards without the gravest solicitude. She was sufficiently shrewd and experienced to appreciate the situation. She reflected that the Bavarian Duke Thassilo, her dead husband’s nephew, without whose consent Charlemagne could not have attained to sovereignty, was as inimical to him as Desiderius was. Thassilo had proved disloyal to Pepin in refusing him the assistance he was in duty bound to furnish in the war against Waisar, Wolf’s predecessor. Bertha knew that death alone prevented her husband from punishing his perfidy. As Thassilo and Desiderius were now on good terms she feared that if Charlemagne should attack the one, the other would come to his help. Besides this, the Saxons to the north of the Frankish kingdom were in arms again. She also feared in case of war that the West-Frankish dukedom would rise again. Lastly, she knew that Desiderius had promised the widow and sons of Carloman to provoke an uprising in their favor in the Frankish kingdom. To avert these dangers Bertha planned to bring Desiderius, Thassilo, and Charlemagne into a tri-partite relationship, and thus establish friendly conditions. She proposed that Charlemagne and Thassilo should marry daughters of Desiderius and that Adalgis, Desiderius’s only son, should marry Gisela, Charlemagne’s sister. The plan was accepted by all concerned except the fair Gisela, who chose to go to a convent and engage in its pious duties, rather than wear a crown.[20] She is honored in the Catholic Church to-day under the name of Itisberg.