TASSILONE II, duke of BAVARIA. — Son of Chiltrude, sister of Pipin the Short, he succeeded his father Odilone through the intervention of his uncle (748); he died c. 13 December 798.
Although he had sworn fealty at Compiègne (757), T. nevertheless did not abandon the idea of making himself independent. During the campaign in Aquitaine, he suddenly left the Frankish army (763) and returned to Bavaria. His reconciliation with Pipin took place in 765 through the mediation of the Pope; but it was not sincere. Charlemagne, mistrusting this vassal of his, required him to swear an oath at Worms (781) and to surrender twelve hostages. T. revealed himself in 786, when his wife Liutberga, daughter of Desiderius, the last King of the Lombards, urged him to betray the Emperor and avenge the defeat of Arechis, duke of Benevento and her brother. T. reached an agreement with the Avars and incited them to fight the Franks; but Charlemagne summoned him to appear at Worms to answer for the crime of lèse-majesté (787). The Duke refused to obey, but the invasion of his territories by the Frankish army compelled him to submit, and at Ingelheim (788) he was condemned to death as a traitor. The sentence, however, was commuted to confinement in a monastery, perhaps that of S. Goar, near Coblenz. In 794 he solemnly renounced all his rights to the Duchy of Bavaria, both in his own name and in that of his sons, who had in any case already been shut up in a monastery (cf. Capitularia regum Francorum, in MGH. ed. A. Boretius-V. Krause, I. Hannover 1883, p. 74, n. 28, art. 3). It is uncertain whether, after this, T. withdrew to the abbey of Jumièges, in Normandy. The chalice offered by T. to Kremsmünster is reproduced at V. CALICE.