The greater part of the English army recrossed the Border, and the Scots captured many of the garrisons left in the towns. Sir John Seagrave next invaded Scotland with from 20,000 to 30,000 men, mostly cavalry. They reached the neighbourhood of Edinburgh, when Comyn and Fraser advanced against them with 8000 men, chiefly infantry. The English army were advancing in three divisions, in order better to obtain provisions and forage. After a rapid night march the Scotch came upon one of them, commanded by Seagrave in person; and conceiving himself sufficiently strong to defeat the Scots unaided by any of the other divisions, Sir John Seagrave immediately gave battle.
As at Falkirk, the English cavalry were unable to break through the Scottish pikes. Great numbers were killed or taken prisoners, Seagrave himself being severely wounded and captured, with twenty distinguished knights, thirty esquires, and many soldiers. Scarcely was the battle over when the second English division, even stronger than the first, arrived on the field. Encumbered by their prisoners, the Scots were at a disadvantage; and fearing to be attacked by these in the rear while engaged in front, they slaughtered the greater portion of the prisoners, and arming the camp followers, prepared to resist the English onslaught. This failed as the first had done; the cavalry were defeated with great loss by the spearmen, and many prisoners taken—among them Sir Ralph Manton.
The third English division now appeared; and the Scots, worn out by their long march and the two severe conflicts they had endured, were about to fly from the field when their leaders exhorted them to one more effort. The second batch of prisoners were slaughtered, and the pikemen again formed line to resist the English charge. Again were the cavalry defeated, Sir Robert Neville, their leader, slain, with many others, and the whole dispersed and scattered. Sir Robert Manton, who was the king's treasurer, had had a quarrel with Fraser, when the latter was in Edward's service, regarding his pay; and Fraser is said by some historians to have now revenged himself by slaying his prisoner. Other accounts, however, represent Manton as having escaped.
The slaughter of the prisoners appears, although cruel, to have been unavoidable; as the Scots, having before them a well appointed force fully equal to their own in number, could not have risked engaging, with so large a body of prisoners in their rear. None of the knights or other leaders were slain, these being subsequently exchanged or ransomed, as we afterwards find them fighting in the English ranks.
Seeing by this defeat that a vast effort was necessary to conquer Scotland, King Edward advanced in the spring of 1303 with an army of such numbers that the historians of the time content themselves with saying that "it was great beyond measure." It consisted of English, Welsh, Irish, Gascons, and Savoyards. One division, under the Prince of Wales, advanced by the west coast; that of the king, by the east; and the two united at the Forth. Without meeting any serious resistance the great host marched north through Perth and Dundee to Brechin, where the castle, under the charge of Sir Thomas Maille, resisted for twenty days; and it was only after the death of the governor that it surrendered.
The English then marched north through Aberdeen, Banff, and Moray into Caithness, carrying utter destruction everywhere; towns and hamlets, villages and farmhouses were alike destroyed; crops were burned, forests and orchards cut down. Thus was the whole of Scotland wasted; and even the rich abbeys of Abberbredok and Dunfermline, the richest and most famous in Scotland, were destroyed, and the whole levelled to the ground. The very fields were as far as possible injured—the intention of Edward being, as Fordun says, to blot out the people, and to reduce the land to a condition of irrecoverable devastation, and thus to stamp out for ever any further resistance in Scotland.
During the three years which had elapsed since the departure of Wallace, Archie had for the most part remained quietly in his castle, occupying himself with the comfort and wellbeing of his vassals. He had, each time the English entered Scotland, taken the field with a portion of his retainers, in obedience to the summons of Comyn. The latter was little disposed to hold valid the grants made by Wallace, especially in the case of Archie Forbes, the Kerrs being connections of his house; but the feeling of the people in general was too strongly in favour of the companion of Wallace for him to venture to set it aside, especially as the castle could not be captured without a long continued siege. Archie and many of the nobles hostile to the claims of Comyn obeyed his orders, he being the sole possible leader, at present, of Scotland. Edward, however, had left them no alternative, since he had, in order to induce the English nobles to follow him, formally divided among them the lands of the whole of the Scotch nobles, save those actually fighting in his ranks.
Archie was now nearly three-and-twenty, and his frame had fully borne out the promise of his youth. He was over the average height, but appeared shorter from the extreme breadth of his shoulders; his arms were long and sinewy, and his personal strength immense.
From the time of his first taking possession of Aberfilly he had kept a party of men steadily engaged in excavating a passage from the castle towards a wood a mile distant. The ground was soft and offered but few obstacles, but the tunnel throughout its whole length had to be supported by massive timbers. Wood, however, was abundant, and the passage had by this time been completed. Whenever, from the length of the tunnel, the workmen began to suffer from want of air, ventilation was obtained by running a small shaft up to the surface; in this was placed a square wooden tube of six inches in diameter, round which the earth was again filled in—a few rapidly growing plants and bushes being planted round the orifice to prevent its being noticed by any passerby.