Before advancing into the pass Bruce detached Douglas, with Sir Alexander Frazer, Sir William Wiseman, and Sir Andrew Grey, with a body of lightly armed infantry and archers. These, unnoticed by the enemy, climbed the side of the mountain, and going far up it, passed along until they got behind and above the enemy. The king ordered his main body to lay aside all defensive armour so that they could more easily climb the hill and come to a hand to hand conflict with the enemy. Then he moved along towards the narrow pass. As they approached it the men of Lorne hurled down a torrent of rocks from the hillside above.
With a few heavy armed men Bruce pushed forward by the water side, while Archie Forbes led the main body up the hillside. The climb was stiff and difficult, and many were swept down by the rocks hurled by the enemy; but at last they came to close quarters with the foe, and a desperate struggle ensued.
In the meantime Douglas and his party had attacked the defenders from the other side, at first showering arrows among them, and then falling upon them with sword and battleaxe. Thus attacked in front and rear, the men of Lorne lost heart and gave way. On both sides the royalists pressed them hotly, and at last they broke from the hillside and fled down to the river, intending to cross by a wooden bridge and destroy it behind them, but before many had passed Douglas with his followers arrived upon the spot and seized the bridge, cutting off their retreat. Great numbers of the men of Lorne were slain, and the survivors made their escape up the mountain side again. The Lornes themselves were on board some galleys on Loch Awe, their intention having been to land in Bruce's rear when he was fairly entangled in the narrow pass. On witnessing the utter discomfiture of their followers they rowed rapidly away, and landed far down the lake. Alexander fled to England, where he ended his life.
Bruce now advanced through the country of Lorne, which, having never suffered from the English raids that had over and over again devastated the rest of Scotland, was rich and flourishing, and large quantities of booty were obtained. Dunstaffnage was besieged and captured, and having received hostages from all the minor chiefs for their good behaviour the king and his army returned to Glasgow.
In the following spring a truce was negotiated by the intervention of the King of France between the belligerents; but its duration was but short, for so long as English nobles held estates and occupied castles in Scotland breaches of the peace would be constantly occurring. Bruce besieged the castle of Rutherglen, near Glasgow; but Edward despatched the Earl of Gloucester to raise the siege, and as Bruce's army was still small he was forced to retire at his approach.
In February, 1309, the clergy of Scotland assembled in a provincial council at Dundee, and issued a declaration in favour of Bruce as lawful king of Scotland. In this document they set forth that although Baliol was made king of Scotland by the King of England, Bruce, the grandfather of the king, was always recognized by the people as being nearest in right; and they said: "If any one, on the contrary, claim right to the aforesaid kingdom in virtue of letters in time passed sealed, and containing the consent of the people and the commons, know ye that all this took place in fact by force and violence, which could not at the time be resisted, and through multiplied fears, bodily tortures, and various terrors."
This document was sealed by all the bishops, as representing the clergy. A similar document was drawn up and signed by the estates of Scotland. Therefore, henceforth Bruce could claim to be the king not only as crowned and by right, but by the approval and consent of the clergy and people of Scotland. A few months afterwards James, the Steward of Scotland, whose course had ever been vacillating, died, and his son Walter, a loyal Scotsman, succeeded him. He afterwards married the king's daughter Marjory, and became the founder of the royal line of Stuart.