Primogeniture, which is practically incompatible with the tribal stage of political organisation, was perhaps formally acknowledged at a very remote period, but was unknown as a rule of succession to Irish chiefries in the ages with which this book chiefly deals. In those comparatively modern times a vacancy was filled from the same family, but the person chosen was generally a brother or a cousin of the deceased. It seldom happened, perhaps, that an Irish chief, who was necessarily a warrior, attained threescore and ten years, and on an average a son would be less likely to make an able leader than one of an older generation. To avoid disputed successions, an heir-apparent, called the tanist, was chosen before a vacancy actually occurred, and sometimes probably against the wish of the reigning chief. Very often the sons refused to accept the tanist, and bloody quarrels followed. This system stank in the nostrils of the Tudor lawyers; but in the twelfth century the true principle of hereditary succession was not fully understood. It was, perhaps, a suspicion that his eldest son might not succeed him quietly that induced Henry II. to crown him in his lifetime. A later and much stronger analogy may be found in the history of the Empire. Charles V. procured the election of his brother Ferdinand as king of the Romans, and he was actually crowned. Many years later Charles wished to substitute his son Philip; but Ferdinand refused to yield, and he was sustained by the electors, who had no mind to see the Empire become an appendage of the Spanish monarchy. The influence of the Irish Brehons probably tended to prevent chiefries from becoming hereditary. In such cases as the earldom of Desmond we have a mixture of the two systems; the earls were chiefs as regarded the Irish; but their succession to the honour, and through it to the quasi-chiefry, was regulated by feudal rules. [Sidenote: Tudor view of the Celtic land law.] As the chief was elected by his tribe from among a limited number, so was the land distributed among the tribesmen within certain fixed limits. As it is with England's treatment of Ireland that we have to do, it may be as well to let Sir John Davies himself say how the matter appeared to the Tudor lawyers:-- [Sidenote: Septs.] 'First be it known that the lands possessed by the mere Irish in this realm were divided into several territories or countries; and the inhabitants of each Irish country were divided into several septs or lineages.' [Sidenote: Lord and tanist.] 'Secondly, in every Irish territory there was a lord or chieftain, and a tanist who was his successor apparent. And of every Irish sept or lineage there was also a chief, who was called Canfinny, or head of a "cognatio."' [Sidenote: Tanistry and gavelkind.]