Soon after his return from this expedition, he was elected governor of Scotland, and his measures in this high office appear to have been judicious and temperate. But the haughty barons could not bear the superiority of one whose only claim was in his merit, and thus division was sown in the Scottish councils at the time when unanimity was more than ever needed. In the summer of 1298 Edward himself invaded Scotland at the head of a powerful army. The plan adopted by Wallace upon this occasion was the same as that which was afterwards so successfully executed by Bruce. He avoided a general battle, which with an army far inferior to the English must have been fought to a disadvantage,—he fell back slowly before the enemy, leaving some garrisons in the most important castles, driving off all supplies, wasting the country through which the English were to march, and waiting till the scarcity of provisions compelled them to retreat, and gave him a favourable opportunity of breaking down upon them with full effect.[62] They advanced unopposed, therefore, but found an inhospitable desert; and Edward, unable to replace his exhausted stores, was at length compelled to issue orders for a retreat to Edinburgh, hoping to meet his fleet at Leith, and then to recommence offensive warfare. At this critical juncture, when the military skill and wisdom of the dispositions made by Wallace became apparent, and when the moment to harass and destroy the invading army in its retreat had arrived, the treachery of her nobles again betrayed Scotland to the enemy. Two Scottish lords, Patrick, Earl of Dunbar, and the Earl of Angus, at day–break privately sought the quarters of the Bishop of Durham, and informed him that the Scots were encamped not far off in the forest of Falkirk. The Scottish earls, who dreaded the resentment of Edward on account of their late renunciation of allegiance, did not venture to seek the king in person. They sent their intelligence by a page, and added, that having heard of his projected retreat, it was the intention of Wallace to surprise him by a night attack. Edward, on hearing this welcome news, could not conceal his joy. “Thanks be to God,” he exclaimed, “who hitherto hath extricated me from every danger. They shall not need to follow me, since I shall forthwith go and meet them.”[63] The consequence of this treachery was the fatal battle of Falkirk, in which the Scots were totally defeated, with vast slaughter, owing to the jealousy and dissensions of the nobility; and Wallace, finding his own exertions thwarted, resigned his office.