The Prince of Aileach now assumed the title of Monarch, and after some short-lived opposition from Roderick O'Conor, his sovereignty was universally acknowledged. From the year 1161 until his death, he might fairly be called Ard-Righ, without opposition, since the hostages of all Ireland were in those last five years in his hands. These hostages were retained at the chief seat of power of the northern dynasty, the fortress of Aileach, which crowns a hill nearly a thousand feet high, at the head of Lough Swilly. To this stronghold the ancestor of Murtogh had removed early in the Danish period, from the more exposed and more ancient Emania, beside Armagh. On that hill-summit the ruins of Aileach may still be traced, with its inner wall twelve feet thick, and its three concentric ramparts, the first enclosing one acre, the second four, and the last five acres. By what remains we can still judge of the strength of the stronghold which watched over the waters of Lough Swilly like a sentinel on an outpost. No Prince of the Northern Hy-Nial had for two centuries entered Aileach in such triumph or with so many nobles in his train, as did Murtogh in the year 1161, But whether the supreme power wrought a change for the worse in his early character, or that the lords of Ulster had begun to consider the line of Conn as equals rather than sovereigns, he was soon involved in quarrels with his own Provincial suffragans which ended in his defeat and death. Most other kings of whom we have read found their difficulties in rival dynasties and provincial prejudices; but this ruler, when most freely acknowledged abroad, was disobeyed and defeated at home. Having taken prisoner the lord of Ulidia (Down), with whom he had previously made a solemn peace, he ordered his eyes to be put out, and three of his principal relatives to be executed. This and other arbitrary acts so roused the lords of Leath Conn, that they formed a league against him, at the head of which stood Donogh O'Carroll, lord of Oriel, the next neighbour to the cruelly ill-treated chief of Ulidia. In the year 1166, this chief, with certain tribes of Tyrone and North Leitrim, to the number of three battalions (9,000 men), attacked the patrimony of the monarch—that last menace and disgrace to an Irish king. Murtogh with his usual valour, but not his usual fortune, encountered them in the district of the Fews, with an Inferior force, chiefly his own tribesmen. Even these deserted him on the eve of the battle, so that he was easily surprised and slain, only thirteen men falling in the affray. This action, of course, is unworthy the name of a battle, but resulting in the death of the monarch, it became of high political importance.