The news of this counter-revolution reunited for a moment the barons.
Gloucester joined Earl Simon in calling an autumn Parliament at St.
Alban's, and in summoning to it three knights from every shire south of
Trent. But the union was a brief one. Gloucester consented to refer the
quarrel with the king to arbitration and the Earl of Leicester withdrew in
August to France. He saw that for the while there was no means of
withstanding Henry, even in his open defiance of the Provisions. Foreign
soldiers were brought into the land; the king won back again the
appointment of sheriffs. For eighteen months of this new rule Simon could
do nothing but wait. But his long absence lulled the old jealousies against
him. The confusion of the realm and a fresh outbreak of troubles in Wales
renewed the disgust at Henry's government, while his unswerving
faithfulness to the Provisions fixed the eyes of all Englishmen upon the
Earl as their natural leader. The death of Gloucester in the summer of 1262
removed the one barrier to action; and in the spring of 1263 Simon landed
again in England as the unquestioned head of the baronial party. What
immediately forced him to action was a march of Edward with a body of
foreign troops against Llewelyn, who was probably by this time in
communication if not in actual alliance with the Earl. The chief opponents
of Llewelyn among the Marcher Lords were ardent supporters of Henry's
misgovernment, and when a common hostility drew the Prince and Earl
together, the constitutional position of Llewelyn as an English noble gave
formal justification for co-operation with him. At Whitsuntide the barons
met Simon at Oxford and finally summoned Henry to observe the Provisions.
His refusal was met by an appeal to arms. Throughout the country the
younger nobles flocked to Simon's standard, and the young Earl of
Gloucester, Gilbert of Clare, became his warmest supporter. His rapid
movements foiled all opposition. While Henry vainly strove to raise money
and men, Simon swept the Welsh border, marched through Reading on Dover,
and finally appeared before London.