 In 855 King Æthelwulf appointed his son Æthelbald to act as king while he went on pilgrimage to Rome, and when he returned the next year Æthelbald refused to give up the throne.Asser, who strongly disapproved of Æthelbald's conduct, stated that the plot was hatched by Æthelbald and his co-conspirators, the bishop of Sherborne and the ealdorman of Somerset, "in the western part of Selwood".Their motives are not known, but one factor may have been resentment of western nobles at the favour Æthelwulf had shown to Winchester and its bishop in eastern Wessex.