We have seen {Book I) that, according to the old Irish system the land of a clan was considered as fundamentally belonging, in its several portions, to the family groups, which, taken together, constituted the State. The chief’s mensal land was ultimately the property of the State as a whole. It was an appanage of the chieftaincy, and, on the death of an occupant, passed to the elected successor. However much the custom of limiting the succession in practice to the members of one family had obscured this notion, it was still present to the minds of the people, and a verbal or practical denial of it would be resented.

In the agreements made between the chiefs and Henry VIII the communal ownership of the lands was not indeed denied, nothing was said regarding it. All that was specifically done, with regard to possessions other than the mensal lands, was to give the chief a right under English law to the powers over them which previously he had exercised without it. Of his mensal lands he was now constituted absolute owner, and they were to be transmitted by primogeniture to his heirs. A few clans had been in the habit of practising primogeniture, but the great majority had not, preferring usually a brother or a nephew, the son of an elder brother, to the son of a deceased chief. In these clans the introduction of the new succession law became a fertile source of dispute. Again, from regarding himself as absolute owner of the mensal land to regarding himself as absolute owner of the rest of the clan territory, and the clansmen as merely his tenants, was, for an ambitious chief, an easy step, and one which English officials often, when it suited them, encouraged him to take. The chiefs who had bound themselves by these agreements would now, if they failed to carry out the conditions contained in them, and especially if they rebelled against the English Crown, be liable certainly to forfeit their mensal lands ; it might be convenient to pretend to consider that the whole of the clan land was also theirs, and so forfeit also.