In the meantime John had been viewing the victorious career of his son-in-law with surprise and displeasure. A strong and united Wales was a thing which no king of England could tolerate. In the third period of his reign, therefore, between 1212 and 1215, we find John and Llewelyn in opposition to one another. Twice in the course of one summer did John invade North Wales, penetrating on the second occasion as far as Bangor, where, characteristically enough, he burned the Cathedral, and held the Bishop to ransom. So hard pressed was Llewelyn that he was obliged to send Joan to make full submission to {75} her father on his behalf. But the tide soon turned. The other Welsh chieftains were greatly alarmed at John's manifest intention to dispossess them; and placing themselves under Llewelyn they begged him to lead them. John had also quarrelled with Rome; and the great Innocent III, who then held the Papacy, absolved Llewelyn and the other Welsh princes from their allegiance to the English king. Events in England were also most propitious; for John had by now come into serious conflict with his own nobility, and was soon to be compelled to concede all their demands by the Charter. With the English barons Llewelyn made an alliance; and Magna Carta, when it was eventually signed, contained clauses dealing exclusively with Wales. One of these clauses consisted of a promise that all Welshmen dispossessed of their lands or liberty should recover them. Another declared that all disputes were to be decided in England by English law, in the Marches by March law, and in Wales by Welsh law. In the year 1213 John had convened a council, in which some have seen the germ out of which grew the future English Parliament. The same idea seems to have found place in the mind of Llewelyn; for on two occasions {76} he summoned together all the princes of Wales, and all the wise men. So far as we know there was no process of election, and certainly no trace of the principle of representation; nevertheless this council was a distinct advance politically upon anything that had been seen in Wales before. The princes were to act as judges, and all questions of policy were to be debated by them with the assistance of the wise men. The first of these councils assembled at Aberdovey, a convenient meeting-place for Gwynedd, Powys, and the South. The decrees of the council were to be upheld by force; and when Gwenwynwyn of Powys soon after refused to obey, he was instantly crushed and deprived of his lands.