Historian Oscar de Ville discusses the career of John Deyville and his brother Robert, along with their kinsmen Jocelin and Adam, during the Second Barons' War, specifically their activities after the Battle of Evesham. John Deyville was granted authority by the faction led by Simon de Montfort, 6th Earl of Leicester over York Castle and the Northern Forests during the war in which they sought refuge after Evesham. John, along with his relatives, led the remaining rebel faction on the Isle of Ely following the Dictum of Kenilworth. De Ville connects their presence there with Bower's mention of "Robert Hood" during the aftermath of Evesham in his annotations to the "Scotichronicon".