But Derry had other enemies than the Danes. In 1124 we find "Ardgar, Prince of Aileach, killed by the ecclesiastics of Doire-Columbkille in the defence of their church. His followers in revenge burned the town and churches." The then abbot was St. Gelasius, who, after presiding sixteen years over the monastery, which he had entered a novice in early youth, was, in 1137, raised to the Primatial See of Armagh; and dying in 1174, nearly closes the long calendar of Irish Saints. The first year of his abbacy (1121) had been marked by the death in the monastery of "Domwald Magloughlin Ardrigh of Erin, a generous prince, charitable to the poor and liberal to the rich, who, feeling his end approaching, had withdrawn thither,"--a fact which shows the great veneration in which this monastery was held. The name of the next abbot, Flathbert O'Brolcan, or Bradley, is one of the brightest in the Annals of Derry. He was greatly distinguished for his sanctity and learning, but still more for his administrative abilities. As abbot of Derry he was present at the Synod of Kells in 1152. Six years after, at the Synod of Brightaig (near Trim, county Meath), a continuation or prorogation of that of Kells, Derry was created an Episcopal See and Flathbert appointed its first bishop. A much more honorable distinction was given him, when by the same synod, he was appointed "prefect general of all the abbeys of Ireland," an appointment which must probably be limited to the Columbian Abbeys, which were at the time very numerous. Some idea of the wealth and power of the Columbian order may be gathered from the records that the Masters have given us of Flathbert's visitations. "In 1150 he visited Tireoghain (Tyrone), and obtained a horse from every chieftain; a cow from every two biataghs; a cow from every three freeholders; a cow from every four villeins; and twenty cows from the king himself; a gold ring of five ounces, his horse and battle-dregs from the son of O'Lochlain, king of Ireland." "In 1153 he visited Down and Antrim and got a horse from every chieftain; a sheep from every hearth; a horse and five cows from O'Dunlevy, and an ounce of gold from his wife." And in 1161 he visited Ossory, and "in lieu of the tribute of seven score oxen due to him, accepted four hundred and twenty ounces of pure silver." But though thus honored by the hierarchy and people, enemies were not wanting to him. In 1144 the monastery had been burned and hostile clouds were again gathering round it, when in 1163 Flathbert erected a cashel or series of earthen fortifications, which baffled for a time the enmity of the plunderer. A passing calm was thus assured him, of which he took advantage, in 1164, to commence the building of his Cathedral, called in Irish "Teampull-mor," a name which one of the city parishes still retains. But the times were troublous, and hardly was the Cathedral finished than we find in 1166 "O'More burning Derry as far as the church Dubh-Regles."