We have thus traced to the third generation the political fortunes of the family of Brian, which includes so much of the history of those times. That family had become, and was long destined to remain, the first in rank and influence in the southern half-kingdom. But internal discord in a great house, as in a great state, is fatal to the peaceable transmission of power. That "acknowledged right of birth" to which a famous historian attributes "the peaceful successions" of modern Europe, was too little respected in those ages, in many countries of Christendom—and had no settled prescription in its favour among the Irish. Primogeniture and the whole scheme of feudal dependence seems to have been an essential preparative for modern civilization: but as Ireland had escaped the legions of Rome, so she existed without the circle of feudal organization. When that system did at length appear upon her soil it was embodied in an invading host, and patriot zeal could discern nothing good, nothing imitable in the laws and customs of an enemy, whose armed presence in the land was an insult to its inhabitants. Thus did our Island twice lose the discipline which elsewhere laid the foundation of great states: once in the Roman, and again in the Feudal era. CHAPTER II. THE CONTEST BETWEEN THE NORTH AND SOUTH—RISE OF THE FAMILY OF O'CONOR. Four years before the death of Thorlogh O'Brien, a Prince destined to be the life-long rival of his great son, had succeeded to the kingship of the northern tribes. This was Donald, son of Ardgall, Prince of Aileach, sometimes called "O" and sometimes "Mac" Laughlin. Donald had reached the mature age of forty when he succeeded in the course of nature to his father, Ardgall, and was admitted the first man of the North, not only in station but for personal graces and accomplishments; for wisdom, wealth, liberality, and love of military adventure.