And the words express sufficiently well the popular opinion of Scotland as the especial and persevering enemy of England. Like a good many popular opinions, it is only partly true. Yet it has a foundation of fact, in so far that for some three centuries England and Scotland were generally at war. Still, this condition of chronic hostility was not reached until the reign of Edward I., and before then the two countries had no more than the amount of warfare that might have been expected of two adjacent and warlike peoples. It has already been noticed that Constantine III.’s vague acknowledgment of English suzerainty had had less success from the political point of view than he had hoped for, and that his attempt to unite the disaffected sections of the English Empire had met with crushing disaster. The old King, bereaved and broken-hearted, withdrew to ‘his northland,’ and for many years the Scottish kingdom, slowly growing together out of its discordant elements of Scots, Picts, and Strathclyde Britons, was content to remain a sort of appendage of its powerful neighbour. But with the break-up of the English Empire in the beginning of the eleventh century, the unsubstantial allegiance of Scotland grew more than ever shadowy. In 1018 occurred an event which had consequences of profound importance. England had just come under the rule of Cnut. Deira was governed by Eric Haakonson, but the Bernicians held out against him under Eardwulf ‘Cudel.’ Malcolm II. of Scotland, a vigorous ruler, saw his chance. He had long coveted Lothian, and had made various futile attacks upon it. In 1006 he had pushed southward as far as Durham, and had there been defeated by Earl Uhtred. But this time he was more fortunate. Eardwulf, attacked by Eric, had more upon his hands than he could cope with, when Malcolm with his vassal, Eugenius of Strathclyde, invaded Bernicia. He overran Lothian without assistance, and at Carham, on the Tweed, gained a crushing victory over the weak Bernician host, almost exterminating it. The result of the victory was the permanent union of Lothian to Scotland. To Cnut it was a matter of small importance; probably he regarded it as better that Lothian should belong to the apparently loyal Scot than the rebellious Eardwulf. In 1027 Malcolm paid a formal homage to the Emperor of the North. But the Lothians and the Merse became an integral part of Scotland, and their sturdy Teutonic population proved the nucleus about which the inchoate and distracted realm eventually solidified into a single state.