busied themselves with repairing the walls of London, using for the purpose the stones taken from the demolished houses of the Jews. In June, John met the barons at Runnymede, where the two sides agreed to the Great Charter, and the barons renewed their vows of fealty. In its final draft Magna Carta contained a clause prohibiting sentences of exile, except as the result of a lawful trial, which refers more particularly to Fitzwalter's case. Fitzwalter was one of the twenty-five executors appointed to see that its provisions were really carried out. For a short time nominal peace prevailed, and Fitzwalter now got back the custody of Hertford Castle. But the barons remained under arms, and Fitzwalter was still acting as "Marshal of the Army of God and Holy Church". He now made a convention with John, by which London remained in the barons' hands till 15 August. But Fitzwalter was so fearful of treachery that within a fortnight of the Runnymede meeting he thought it wise to postpone a tournament fixed to be held at Stamford on the Monday after the feast of Saints Peter and Paul (29 June) for another week, and chose as the place of its meeting Hounslow Heath, that the barons might be near enough to protect London. First Barons' War On 26 August, John and the barons tried to arrange at a meeting at Staines. When this failed, the First Barons' War broke out. The twenty-five executors assigned to themselves various counties to secure them for their side. Fitzwalter, who with Eustace de Vesci was still the leading spirit of the movement, became responsible for Northamptonshire. On 17 September John granted Fitzwalter's Cornish estates to his young son Prince Henry. But the pope's annulling the charter had paralysed the clerical supporters of the popular side, and the thoroughgoing policy of the twenty-five under Fitzwalter's guidance had alienated of the more moderate men. Fearing Archbhishop Langton might be forced to surrender his castle of Rochester, Fitzwalter, with the assent of the warden of the castle, Reginald de Cornhill, secretly occupied it with a large force. John's troops soon approached, and strove, by burning Rochester bridge and occupying the left bank of the way, to cut off Fitzwalter from his London confederates. But Fitzwalter succeeded keeping his position, though before long he was forced on 11 October to retreat to London, allow the royalists to occupy