In 915 the area faced an incursion from Vikings led by and Hroald, coming from the River Severn. After first capturing Cyfeiliog (Cimeliauc), the Bishop of Llandaff, they were defeated in battle by the combined forces of Gloucester and Hereford, possibly at "Kill Dane Field" near Weston-under-Penyard. According to one of the "Anglo-Saxon Chronicles", Cyfeiliog, referred to as Cameleac in the Worcester Chronicle, was bishop in Archenfield, and King Edward the Elder ransomed him for £40, but in the view of Michael Swanton the evidence for a bishopric there is weak, and the text can be read that he was taken in Archenfield. Thomas Charles-Edwards refers to "Bishop Cyfeilliog, who was probably bishop of Ergyng, or at least captured in Ergyng". He sees the payment of a ransom by the West Saxon king as evidence that the far south-east of Wales then lay in the sphere of power of Wessex rather than Mercia.