Ireland was older than the Gaelic occupation. In fact, its origin was prehistoric, and the Pentarchy is the oldest certain fact in the political history of Ireland. That it is a certain fact, nobody who is acquainted with Irish literature and tradition will be disposed to question. To this day the word _cuigeadh_, "a fifth," is in general use among speakers of Irish as the term to denote each of the principal sub-divisions of the country; and _cuig cuigidh na hEireann_, "the Five Fifths of Ireland," is an expression familiar to all who speak the Irish language. This term _cuigeadh_, in this sense, is found in every age and generation of our written literature. And yet it is certain that throughout the whole period of our written literature, the political division of Ireland represented by this word _cuigeadh_, "a fifth," and "the Five Fifths of Ireland," had no existence. Already in St. Patrick's time the Five Fifths were only a memory of the past. Then and for centuries afterwards, instead of five, there were seven coordinate chief kingdoms and a monarchy over them. It is evident that a political fact which impressed itself so permanently on the vocabulary, the literature, and the folk-memory of the people for at least fifteen hundred years was not the transitory thing that appears in the lists of Irish monarchs before Christianity, a Pentarchy which lasted only during a few years and interrupted for that time the course of an earlier and later Monarchy. The details of tradition, upon examination, indicate that the Pentarchy preceded the Monarchy and lasted for a long time, long enough to become the chief outstanding fact in tradition as regards the internal political state of Ireland in the early Celtic period. Now we come to the question, what were the five principal divisions of Ireland under the Pentarchy? In my experience, the less erudite who are interested in such matters usually answer, Ulster, Leinster, Munster, Connacht and Meath. Those who are better read in Irish history will answer, as a rule, leaving out Meath and will say that there were two Fifths comprised in Munster, and this is the teaching of Irish historians for some centuries back. In this case, it will be seen that the less learned folk are nearer to the truth.