Roger, who was to bring his force from the west to join Ralph, was held in check at the River Severn by the Worcestershire fyrd which the English bishop Wulfstan brought into the field against him. Ralph in the meantime encountered a much superior force under the warrior bishops Odo of Bayeux and Geoffrey de Montbray (the latter ordered that all rebels should have their right foot cut off) near Cambridge and retreated hurriedly to Norwich, hotly pursued by the royal army. Leaving Emma to defend Norwich Castle, Ralph sailed for Denmark in search of help. He eventually returned to England with a fleet of 200 ships under Cnut and Hakon, but they failed to do anything effective.