Charles, childless by his marriage to Richgard, tried to have his illegitimate son by an unknown concubine, Bernard, recognised as his heir in 885, but this met with opposition from several bishops. He had the support of Pope Hadrian III, whom he invited to an assembly in Worms in October 885, but the pope died on the way there, just after crossing the river Po. Hadrian was going to remove the obstructing bishops for Charles, as he doubted he could do this himself, and legitimize Bernard. Based on the unfavouring attitude shown by the chronicler responsible for the Mainz continuation of the "Annales Fuldenses", the chief of Charles's opponents in this matter was most likely Liutbert, Archbishop of Mainz. Because Charles had called together the "bishops and counts of Gaul" as well as the pope to meet him at Worms, it is likely that he had plans to make Bernard King of Lotharingia. Notker the Stammerer, who considered Bernard as a possible heir, wrote in his "Deeds of Charlemagne":