The next two centuries added Ferns, Cork, Killaloe, and eleven other sees, with their cathedrals and churches, and fifty-five principal schools, monasteries, and abbeys. During the ninth and tenth centuries we find only two sees created, and no mention of additional monasteries or schools. This may be accounted for by the continual incursions of the Northmen, a swarm of barbarians whose native element seems to have been the ocean and whose only end and object were bloodshed and rapine. From 807 until the decisive battle of Clontarf in 1012, they perpetrated an uninterrupted series of raids on Ireland, and even sometimes held the larger portion of the country in subjection. Landing from their ships at remote and undefended points on the coast, they marched stealthily into the interior, marking their paths with the blood of the defenceless inhabitants, sparing neither age, sex, nor condition in their fury, and bearing off or destroying every species of property. Churches were given to the flames, the relics of the saints stolen or scattered to the winds, monks, nuns, and students put to the sword without mercy or remorse. In one of those incursions Bangor was plundered and nine hundred monks slaughtered. Armagh was sacked and its cathedral destroyed. Cork, Ferns, and Taghmon shared the same fate, while the city of Kildare, its cathedral and nunnery were razed, and their inhabitants massacred or carried into slavery. Clonmacnois was thirteen times plundered, and scarcely a religious house on the island but received at least one visit from the sacrilegious invaders.
After a long and brilliant career an eclipse seemed to have fallen on the church in Ireland, her monasteries were in ruins, her priesthood slaughtered, and her schools deserted. But the genius of one great man was put forth to save the people. Brian, surnamed Boroimhe, King of Munster, and monarch of Ireland, after repeated victories drove the Danes out of his kingdom, and, finally, by his last great battle, destroyed their power for ever in Ireland. The remnant of the once dreaded enemy, embracing the faith of their conquerors, were permitted, upon paying tribute, to settle along the coast for the purpose of foreign traffic. This great king during his long reign did much to reinstate the church in possession of her property, and to repair the damages of two centuries of organized plunder, and his successors continued to follow his example. Even the converted Danes imbibed the prevailing spirit of restitution. The see of Dublin was established in 1040, and its cathedral, consecrated to the Holy Trinity, (now Christ's church,) was built by Bishop Donatus. The see of Waterford was founded in 1096, and its splendid cathedral, also under the invocation of the Holy Trinity, erected by Malchus, its first bishop; and the celebrated priory of Selsker, in Wexford, was established by the new converts some few years afterward. The see of Ardfert was founded in the middle of the eleventh century, and that of Derry about one hundred years subsequently.
It is reasonable to infer that most of the early Irish ecclesiastical structures of any magnitude were of wood, with perhaps a stone tower or stronghold to serve as a depository for sacred vessels, libraries, etc., and for defence in case of actual attack. Dr. Petrie, in his great book on Round Towers, produces convincing proofs that these curious specimens of architecture, some seventy of which still remain more or less well preserved, were intended for these purposes. Ireland at the time of Saint Patrick was densely wooded, oak being predominant, and where so many extensive buildings had to be erected in so limited a time no more convenient and suitable, though certainly very destructible, material could be used. This, as well as the ravages of time and foreign invasion, will explain the fact that so many of the sites of our primitive edifices are recognized only by local tradition. The art of building in stone was indeed known in the country before the introduction of Christianity, but it was not generally applied to church purposes till about the beginning of the twelfth century.
When Cormac McCulinan was appointed to the see of Cashel, it is recorded that he built a cathedral in that city in the latter part of the ninth century, which, according to the annals of the priory of the Island of all Saints, was not long after rebuilt and consecrated with great ceremony. Whether the beautiful ruin now called Cormac's chapel owes its origin to the warrior bishop or to a successor of the same name is a mooted question among antiquarians, as the records of the succession in this diocese are very imperfect. However, it must have been erected at an early age, for we find that in 1170 Donald O'Brian, King of North Munster, built the cathedral of St. Patrick in his royal city of Cashel, and the former church of Cormac was converted into a chapter-house, on the south side of the choir. Bishop O'Heden in 1420 repaired and beautified St. Patrick's and erected a hall for the vicars choral. In the same year that Donal O'Brian built St. Patrick's he also caused to be constructed the beautiful cathedral of St. Mary's in Limerick, endowing it liberally, and it existed in great splendor until the Reformation, when it shared the general fate of all such noble institutions.
The cathedral of St. Patrick, in Down, was rebuilt on the site of the old one by St. Malachy in 1138, and forty years afterward was enlarged by one of his successors and a namesake. About this time it was dedicated to St. Patrick, having been formerly consecrated to the Most Holy Trinity, a favorite name, it would appear, for cathedrals in the early centuries of Christianity.
St. Mary's, at Tuam, was built in 1152, by O'Connor, King of Ireland, and Bishop O'Hoisin, the first archbishop of that see; in 1260 it was enlarged and a new choir added. Finally, it was given over by Henry VIII. to an apostate named Bodkin.
St. Columba's, in Derry, was built in 1164, by King Maurice MacLaughlin. It also had to succumb to the reformers who settled in Ulster, and the present Protestant cathedral of that town was built on its ruins, by the "London Company," in 1633.
The majestic cathedral of Kilkenny, dedicated to St. Canice, was commenced in 1178, by Bishop Felix O'Dullany, and was finished by Bishop St. Leger in 1286. Some years later it was altered and beautified by Bishop Ledred, and at the time of the Reformation was considered one of the most beautifully situated buildings in Europe.
The cathedral of the Holy Trinity, in Waterford, was built about the beginning of the eleventh century. Its subsequent fate is thus related by a recent Protestant writer: [Footnote 301]
[Footnote 301: Ireland and her Churches, by James Godkin.]