For the next three months, he stayed in Stoubes. Roger had been sent off at once, with two men-at-arms, to bring the horses and armour that had been left at Welshpool; bearing a letter to the governor from Oswald, thanking him much for having taken care of them, and saying briefly that he had been left on the field for dead, after the fight near Llanidloes; but had recovered, and been well treated by Glendower, who had put him to ransom. He took money with him, to pay the expenses for the keep of the horses; and returned, with them and the armour, after an absence of three weeks. Passing through Worcester on his way back, he had, at Oswald's order, purchased for himself clothes suitable for his position as an esquire. As for armour, it had been arranged that he should have it made for him at Alnwick, as it would be difficult to obtain a suit sufficiently large for him. At the end of the three months the necessary repairs to the castle were finished. The gates had been greatly strengthened with thick bands of iron, the moat cleared out, and at various points the defences had been strengthened. The small amount of furniture then deemed necessary still remained there and, where needful, had been repaired and put in good order. Eight men-at-arms had been taken by Oswald into his service, and a trusty man appointed as seneschal. Then, after paying another visit to Yardhope, Oswald rode, with Roger and two well-mounted men-at-arms, to Alnwick. It was now April, and bad news had just arrived. Glendower had commenced the campaign with great vigour, as the appearance of a comet had been interpreted, by the bards, as an omen most favourable to him, and his force had greatly increased during the winter. He had destroyed the houses and strong places of all Welshmen who had not taken up arms at his orders, and had closely blockaded Carnarvon. He marched to Bangor, levelled the cathedral, and that of Saint Asaph, by fire, burnt the episcopal palaces and canons' houses. So formidable did he become that the king issued writs, to the lieutenants of no fewer than thirty-four counties, to assemble their forces at Lichfield, to crush Glendower. The latter had now taken the offensive, and advanced towards Hereford, and carried fire and sword through Mortimer's lands. Sir Edmund gathered his own and his nephew's tenants and retainers, from Herefordshire and Radnorshire, and advanced against Glendower. The armies met on the 22nd of June, 1402, at a short distance from Knighton. The battle was obstinately fought, but was decided by the desertion of the Welsh tenants, and by the Welsh bowmen in Mortimer's service turning their bows against his men-at-arms; and, finally, the English were defeated, with the loss of eleven hundred men, Sir Edmund himself being made a prisoner.