In 770, his mother Bertrada began a series of diplomatic offensive to encircle Carloman. Charlemagne had married Desiderata, the daughter of the Lombard king Desiderius in Italy, which created an alliance between Charlemagne and the Lombards; Bertrada had also secured for Charlemagne the friendship of Tassilo, Duke of Bavaria, her husband's nephew; she had even attempted to secure Papal support for the marriage by arranging for Desiderius to cede certain territories to Rome, to which the Papacy laid claim. Although Pope Stephen III remained hostile to an alliance between the Franks and the Lombards in theory, in reality, he was deeply conflicted between the threat the Lombards posed to him and the chance to dispose of the anti-Lombard Christopher the "Primicerius", the dominant figure at the Papal court.