Glyndwr now fell with heavy hand upon this southern country, crossing the headwaters of the Severn and the Wye, and pressing hard upon the Marches of Carmarthen. The common people rose on every side and joined the forces that acted either under his leadership or in his name. Those who did not join him, as was certainly the case with a majority of the upper class at this early period, had to find refuge in the castles or to fly to safer regions, leaving their property at the mercy of the insurgents. But a battle was fought at the opening of this campaign on the summit of Mynydd Hyddgant, a hill in the Plinlimmon group, that did more, perhaps, to rouse enthusiasm for Glyndwr than even the strains of the bards or his own desolating marches.
The Flemings in Wales at that time were not confined to Western Pembroke, but had still strong colonies below Carmarthen, in the Glamorgan promontory of Gower, and some footing in South Cardiganshire. Whether they had actually felt the hand of Glyndwr upon their borders, or whether they deemed it better to take the initiative, they at any rate collected a force of some fifteen hundred men, and marching northward to the Cardigan mountains, surprised the Welsh leader as he was encamped on the summit of Mynydd Hyddgant, with a body of less than five hundred men around him. The Flemish strategy was creditable, seeing that it was carried out by slow-witted and slow-footed lowlanders against nimble mountaineers and so astute a chieftain. Owen found himself surrounded by a force thrice the number of his own, and either death or capture seemed inevitable. As the latter meant the former, he was not long in choosing his course, and putting himself at the head of his warriors he attacked the Flemings with such fury that he and most of his band escaped, leaving two hundred of their enemies dead upon the mountain slope. This personal feat of arms was worth five thousand men to Owen. It was all that was wanted to fill the measure of his prestige and decide every wavering Welshman in his favour.
For this whole summer Glyndwr was fighting and ravaging throughout South and Mid-Wales. The lands of the English as well as of those Welshmen who would not join him were ruthlessly harried. Stock was carried off, homesteads were burned, even castles here and there were taken, when ill-provisioned and undermanned. New Radnor under Sir John Grendor was stormed and the sixty defenders hung upon the ramparts by way of encouragement to others to yield. The noble abbey of Cwmhir too, whose ruins still slowly crumble in a remote Radnorshire valley, felt Glyndwr’s pitiless hand, being utterly destroyed. His animosity to the Church was intelligible, though for his method of showing it nothing indeed can be said. The Welsh Church, though its personnel was largely native, was, with the exception of the Franciscan order, mostly hostile to Glyndwr and upon the side of the English Government. Bards and priests, moreover, were irreconcilable enemies. The latter had in some sort usurped the position the former had once held, and now the patron and the hero of the bards, who were once more lifting up their heads, was not likely to be acceptable to the clergy. This, however, would be a poor excuse for an iconoclasm that would set a Welsh torch to noble foundations built and endowed for the most part with Welsh money.
Glyndwr in the meantime swept down the Severn valley, burning on his way the small town of Montgomery, and coming only to a halt where the border borough of Welshpool lay nestling between the high hills through which the Severn rushes out into the fat plains of Shropshire.
The great Red Castle of Powys, then called “Pole,” overlooked in those days, as it does in these, the town it sheltered. The famous Shropshire family of Charlton were then, and for generations afterwards, its lords and owners. From its walls Glyndwr and his forces were now driven back by Edward Charlton with his garrison and the levies of the neighbourhood, which remained throughout the war staunch to its lord and the King. The repulse of Owen, however, was not accomplished without much hard fighting and the destruction of all the suburbs of the town.
But these sallies from castles and walled towns could do little more than protect their inmates. Mid- and South Wales literally bristled with feudal castles containing garrisons of, for the most part, less than a hundred men. These scattered handfuls were unable to leave their posts and act in unison, and when the abandonment of North Wales by Hotspur gave further confidence to those who had risen, or would like to rise, for Glyndwr, the greater part of South Wales fell into line with the Centre and the North. From the border to the sea Owen was now, so far as the open country was concerned, irresistible. Nor was it only within the bounds of Wales that men who were unfriendly to Glyndwr had cause to tremble. The rapid progress of his arms had already spread terror along the border, and created something like a panic even in England. The idea of a Welsh invasion spread to comparatively remote parts, and urgent letters carried by hard-riding messengers went hurrying to the King from beleaguered Marchers and scared abbots, beseeching him to come in person to their rescue.
All this happened in August. As early as the preceding June, when Conway was in Welsh hands, the King had meditated a second invasion in person, and had issued summonses to the sheriffs of fourteen counties to meet him at Worcester, but the approaching surrender of Conway and the optimistic reports from Wales that met him as he came west turned him from his purpose. There was no optimism now; all was panic and the King was really coming. The Prince of Wales in the meantime was ordered forward with the levies of the four border counties, while the forces of twenty-two of the western, southern, and midland shires were hurriedly collected by a proclamation sent out upon the 18th of September.
One reads with constant and unabated surprise of the celerity with which these great levies gathered from all parts of the country to the appointed tryst, fully equipped and ready for a campaign. One’s amazement, however, is sensibly modified as the narrative proceeds and discovers them after a week or two of marching in an enemy’s country reduced to their last crust, upon the verge of disaster and starvation, and leaving in their retiring tracks as many victims as might have fallen in quite a sharp engagement.
By the opening of October the King and Prince Henry had entered Wales with a large army. The proclamation of September the 18th, calling out the forces of England, had stated that the greater part of the able-bodied men of Wales had gone over to Owen. Now, however, as this great host pushed its way to Bangor, as had happened before, and would happen again, not a Welshman was to be seen. On every side were the sparse grain-fields long stripped of their produce, the barns empty, the abundant pastures bare of the small black cattle and mountain sheep with which in times of peace and safety they were so liberally sprinkled. On the 8th of October the army was at Bangor, on the 9th at Carnarvon, whose tremendous and impregnable fortress John Bolde defended for the King with about a hundred men. Still seeing no sign of an enemy, they swept in aimless fashion round the western edges of the Snowdon mountains (for the route through them, which was even then a recognised one, would have been too dangerous), arriving in an incredibly short space of time in Cardiganshire, where the King called a halt at the great and historic abbey of Ystradfflur or Strata Florida.
The weather for a wonder favoured the English, and we might be excused for giving our imagination play for a moment and painting in fancy the gorgeous sight that the chivalry of half England, unsoiled by time or tempests or war, with its glinting steel, its gay colours, its flaunting pennons, shining in the October sun, must have displayed as it wound in a long, thin train through those familiar and matchless scenes. The great Cistercian house of Ystradfflur had shared with Conway in olden days the honour of both making and preserving the records of the Principality. Around the building was a cemetery shaded by forty wide-spreading and venerable yew trees. Beneath their shade lay the bones of eleven Welsh Princes of the twelfth and thirteenth centuries and perhaps those of the greatest Welsh poet of the age, Dafydd ab Gwilim. Henry cared for none of these things. He allowed the abbey to be gutted and plundered, not sparing even the sacred vessels. He turned the monks out on to the highway, under the plea that two or three of them had favoured Owen, and filled up the measure of desecration by stabling his horses at the high altar.