 The baronial army was caught asleep in camp by a surprise attack in the early hours of 1 August and massacred.The survivors took refuge inside the castle and Edward initiated the long Siege of Kenilworth.The elder Simon had taken advantage of Edward's move to Kenilworth to cross the Severn at Kempsey, and was on his way to join his son when he was intercepted and decisively defeated by the royalists in the Battle of Evesham on 4 August.