Creontius provides important information about Tassilo's wars with the Carantanians. He gives an account of Tassilo's meeting with Charlemagne at Worms in 781, reporting that "they concluded an eternal peace with each other". He provides a detailed account of the fighting between the Bavarians and Charlemagne's Italian lieutenant, Rotpert, near Bolzano in the valley of the Adige in 784 or 785, even connecting it with the ongoing rebellion of Widukind: