In Wales the strain of the Saxon wars kept them from their full fruition.  Celtic warfare was governed by a certain code:  thus, you, went to war only at such and such a time of the year; invaded your neighbor’s territory only through such and such a stretch of his frontier; and no one need trouble to guard more than the recognized doorway of his realm.  Above all, you never took an army through church lands.  So through all the wars the Britons might be waging among themselves to keep their hands in, the monastery-colleges remained islands of peace, on friendly terms with all the combatants.  But Wales, with no natural frontier, lay very open to invaders who knew no respect for religion or learning.  Twelve hundred of the student-monks of Bangor, for example, were slaughtered in 613 by the Saxon Ethelfrith;—­whereafter the rest fled to Bardsey Island in Cardigan Bay, and the great college at Bangor ceased to be.

Augustine of Canterbury, sent by the Pope to convert the English, had summoned the Welsh bishops to a conference, and ordered them to come under his sway and conform to Rome.  They hardly knew why, but disliked the idea.  Outwardly, their divergence from Catholicism was altogether trivial:  they had their own way of shaving their heads for the tonsure, and their own times for celebrating Easter,—­though truly, these are the kind of things over which you fight religious wars.  However, it was not these details that worried them so much; but an uneasy sense they derived, perhaps, from the tone of Augustine’s summons.  The story runs that they took counsel among themselves, and agreed that if he were a man sent from God, they would find him humble-minded and mannered; whereof the sign should be, that he would rise to greet them when they entered.  But Augustine had other ideas; and as the ambassador of the Vicar of Christ, rose to greet no man.  So still, not quite knowing why, they would have no dealings with him; and went their ways after refusing to assimilate their Church of the Circled Cross to his of the Cross Uncircled;—­whereupon he, to teach them a sound lesson, impelled the Saxon kings to war.  Fair play to him, he was dead before that war brought about the massacre of the monks of Bangor,—­who had marched to Chester to pray for the Briton arms.

But when Findian went back to Ireland he found no such difficulties in his way.  Not till two hundred and seventy-five years later was that island disturbed by foreign invaders; and whatever domestic Kilkenny Cattery might be going forward, the colleges were respected.  His school at Clonard quickly grew* till its students numbered three thousand; and in the forties, he sent out twelve of the chief of them to found other such schools throughout the island.  Then the great age began; and for the next couple of thirteen-decade periods Ireland was a really brilliant center of light and learning.  Not by any means merely, or even chiefly, in theology; there was a wonderful quickening of mental energies, a real illumination.  The age became, as we have seen, a sort of literary clearing-house for the whole Irish past.  If the surviving known Gaelic manuscripts were printed, they would fill nearly fifty thousand quarto volumes, with matter that mostly comes from before the year 800,—­and which is still not only interesting, but fascinating.