 In 1456 the cathedral chapter of Trier elected John II of Baden against Diether.On 18 June 1459 he was elected the Archbishop of Mainz with a clear majority over Adolph of Nassau-Wiesbaden-Idstein, although never confirmed by the Pope.In 1461 he went to Nuremberg for Imperial and Papal reform, and its recommendations earned him the wrath of both the Emperor Frederick III and Pope Pius II.