=21. Montrose's Campaign.=--Meanwhile Montrose, whose zeal for the Covenant had now changed into zeal for the King, was taking advantage of the absence of the Covenanting force in England to win back the North for Charles with an army of Celts alone. It was the first time that the Highlanders had been turned to account in regular war. Hitherto they had been thought only capable of preying upon one another, but now, under a General who knew how to handle them, they did wonders. The Lowlanders who had hastily mustered to oppose them were beaten at _Tippermuir_. _Montrose_ then took _Perth_, marched northward, again defeated the _Covenanters_, took _Aberdeen_ once more, and held for the King this town which twice before he had held for the Covenant. He then turned to the West, wasted the country of his great enemy _Argyle_, pounced down upon and scattered the force gathered to oppose his own on the shore of Loch Linnhe; kept his army in the Highlands during the winter, and early in the spring took _Dundee_. He twice defeated the Covenanters in the country north of the _Forth_, and once south of it at _Kilsyth_. Thus in a wonderfully short time he won back nearly the whole country for the King. But the secret of his success had lain in the rapid marches and sudden attacks that kept his men busy. When the fighting was over, the Highlanders, as was their wont, went off in large numbers to take home their spoil. In this way his army was diminished. _David Leslie_, who had been summoned home to oppose him, brought some cavalry from the southern army against his weakened force, and won a complete victory at _Philiphaugh_, near _Selkirk_, September 12th, 1645. Montrose retreated with the small remnant that was left to him, but he found it impossible to reassemble his scattered force. His campaign had lasted little more than a year, and a few months later the King, who had thrown himself on the protection of the Scots army at Newark, ordered him to lay down his arms. Montrose obeyed and left the country.