Warenne, Gaveston, and baronial reform

John de Warenne began Edward II's reign as a supporter of the king and witnessed the grant making Piers Gaveston earl of Cornwall. At Gaveston's Wallingford tournament, Warenne and the other earls defeated the favorite, only to see him claim the spoils under tournament custom and create a personal grievance. Warenne then joined the Boulogne agreement and the demand for Gaveston's exile before Henry de Lacy mediated another abrupt reconciliation. Court favor, Scottish war policy, patronage, and personal honor could realign one magnate several times.