By his brother’s retirement Pippin became mayor of Austrasia as well as of Neustria. He had one more struggle to wage ere all things were fully beneath his hand. In 747 his brother Grifo escaped from prison, and fled to Saxony, from whence he tried to stir up trouble. When Odilo duke of Bavaria died, he seized that duchy, claiming it in right of his mother, Swanhildis, who was of the ducal stock. Pippin soon drove him out, and he was constrained to flee to Aquitaine. Bavaria fell to Tassilo, the son of the late duke. After the rebellion of Grifo we read in the Frankish annals the unusual entry, that ‘the whole land had peace for two years’ (749-50). Being now in complete possession of the Frankish realm, and fearing no foe from within or from without, Pippin took the step which must always have been present in the brains of his ancestors, since the day when the over-hasty Grimoald had endeavoured to seize the royal power in 656. Warned by Grimoald’s fate, Pippin the Younger and Charles Martel had scrupulously refrained from claiming the title of king, and had religiously kept up the series of puppet-princes of the old Merovingian stock. Their descendant was now determined to bring the farce to its end, and would not even wait for the death of the imbecile Childerich III., whose vain name had for the last ten years served to head Frankish charters and rescripts. Early in 751 the national council of the whole realm was summoned, and eagerly approved of the removal of Childerich and the election of Pippin as king. To bestow a still greater show of legal authority on the change, Pippin then sent an embassy to Rome to obtain the approval of the Pope. Its leader, Burkhard, bishop of Würzburg, demanded of pope Zacharias ‘Whether it was well or not to keep to kings who had no royal power?’ [Sidenote: Pippin dethrones Childerich III.] The pontiff, whose chief desire was to win aid against the Lombards by flattering the ambition of Pippin, made the answer that was expected of him. ‘It is better,’ he said, ‘that the man who has the real power should also have the title of king, rather than the man who has the mere title and no real power.’ On the receipt of the Pope’s encouraging message, which he regarded as freeing him from any religious obligation resting on oaths sworn to the unfortunate Childerich, Pippin once more summoned the Great Council of the Franks to meet. It assembled at Soissons in October or November 751, and, in the ancient royal city of Neustria, Pippin was first acclaimed as king, and lifted on the shield, after the ancient Teutonic custom, by the unanimous voice of the whole nation, and then anointed, as befitted a Christian sovereign, by the great Austrasian archbishop Boniface. Childerich was shorn of his regal locks, and sent to spend the remainder of his days in an obscure monastery, instead of the hardly less obscure royal manor in which he had hitherto dwelt.