It is indeed wonderful that it should have done so. For the method of the Synod--fixing the number of the dioceses before their boundaries were discussed--was unstatesmanlike. Always, and necessarily, ecclesiastical divisions have coincided with civil divisions. We may find the germ of the rule in the Acts of the Apostles.[53] If this was inevitable in other lands it was even more inevitable in Ireland in pre-Norman days. The Irish people was a collection of clans, having, it is true, certain common institutions, but bound together by no sort of national constitution, and often at war with each other. If ecclesiastical divisions were to be permanent in Ireland, they must take account of the tribal divisions of the country. The primary ecclesiastical unit must be the territory of a tribe, just as it was the primary civil unit.[54] But to base the limits of dioceses, consistently and in every case, on tribal boundaries was impossible when the number of dioceses was arbitrarily fixed beforehand. It could not be that exactly the same number of dioceses would suit Ulster as suited Leinster and Connaught. In one province the tribes would be more or less numerous, and more or less mutually antagonistic, than in another. By reason of its method, therefore, the Synod was doomed to fall short of complete success in its work.
We have instances in Ulster of the soundness of the principle that I have stated. Take the diocese of Raphoe. It was designed to include Inishowen. But from a tribal point of view Inishowen (Inis Eoghain) belonged to the next diocese, which included the tribeland of Tír Eoghain. Its inhabitants were of the same stock as the Cenél Eoghain, and were known as the Cenél Eoghain of the Island. So the natural result followed. Inishowen broke off from the diocese of Raphoe and became part of the diocese of Derry. When this happened the diocese of Raphoe was stabilized. It consisted of the land of a single tribe, the Cenél Conaill; and so henceforth its limits were never altered.
We can easily understand, therefore, that the disregard of tribal boundaries, forced on it in many cases by its method, was an element of weakness in the Rathbreasail scheme. And yet it was natural that special stress should be laid on the arbitrary limitation of sees which was its main cause. Ireland was overrun with bishops. It is said that over fifty of them attended the Synod of Rathbreasail; and they represented only part of the country. But Gilbert had laid down the rule that an archbishop could not have more than twenty suffragans. On this principle, if all the existing bishops had been provided with dioceses, or all the larger tribes had been given bishops, Ireland would have had not two, but six or seven archbishops: and this would have been a travesty of Catholic Church order, as it was then understood. It was essential that the number should be ruthlessly cut down.