 He knew how to make peace, and, if necessary, to wield the sword in self-defence.Sent by Conrad to Robert the Pious, he established so firm a peace between France and the empire that it was not again broken even during the reigns of the sons of both Conrad and Robert.On the other hand, he held his episcopal city against Count Odo II of Blois, a rebel against Conrad, and "by his wisdom and exertions" added Burgundy to the empire.