During the king's absence abroad, the barons' cause was materially strengthened by the support afforded Simon de Montfort, Earl of Leicester, by the king's son. Upon hearing of the defection of his son, Henry hurried back to England. A consultation took place in the city as to the attitude which the citizens ought to take up, with the result that when Henry appeared (April, 1260), both he and the Earl of Gloucester were admitted into the city, whilst the Earl of Leicester and "Sir Edward," as the chronicler styles the king's son, had to find accommodation in the suburbs.(236)
Henry was now master of the situation. The city was his, and he determined that it should remain so. Strict watch was kept over the gates, which for the most part, were kept shut night and day in order to prevent surprise. Every inhabitant of the age of twelve years and upwards was called upon to take an oath of allegiance before the alderman of his ward, and those of maturer age were bound to provide themselves with arms. The king, who now ruled again in his own way, stirred the anger of the barons, by presuming to appoint Philip Basset, his chief justiciar, without first asking their assent; and the barons retaliated by removing the king's sheriffs, and appointing "wardens of the counties" in their stead.(237) In June 1261, Henry produced a Bull of Alexander IV, annulling the Provisions of Oxford, and freeing him from his oath.(238)
For eighteen months the king reigned supreme. The barons could do nothing, and the Earl of Leicester, finding their cause hopeless, withdrew in August (1261) to France, and remained there until the spring of 1263, when he returned as the unquestioned head of the baronial party, to take up arms against the king. The citizens professed loyalty to Henry, who was residing in the Tower, and bound themselves by oath to acknowledge his son Edward as heir to the crown.(239) At Whitsuntide, the barons sent a letter to the king requiring him to observe the Provisions of Oxford, and shortly afterwards, addressed another letter to the citizens "desiring to be certified by them whether they would observe the said ordinances and statutes made to the honour of God in fealty to his lordship the king, and to his advantage of all the realm, or would, in preference, adhere to those who wished to infringe the same."(240)