Deaths Áed mac Boanta, king of Dál Riata Aznar I, king of Aragon Cathal mac Muirgiussa, king of Connacht Chengguan, Chinese Buddhist monk (b. 738) Cummascach mac Congalaig, king of Brega Egbert, king of Wessex Eóganan mac Óengusa, king of the Picts Ibrahim ibn al-Mahdi, Muslim prince (b. 779) Muhammad at-Taqi, Muslim ninth Ismā'īlī imam (or 840) Muiredach mac Eochada, king of Ulaid Pei Du, chancellor of the Tang Dynasty (b. 765) Rorgon I, count of Maine (or 840) Sicard, prince of Benevento Vache, prince of Kakheti Wiglaf, king of Mercia References Sources