In the 6th c. extensive monasteries were founded in Ireland, in which religion learning were zealously cultivated. From these establishments numerous missionarici iesned during the succeeding centuries, carrying the doctrines of Christianity uncle' great difficulties into the still pagan countries of Europe, whose inhabitants they stir. prised and impressed by their self-devotion and ascetism. Many students of distinction from England and the continent frequented Ireland, and received gratuitous instruction at this period. To these ages has been ascribed the origin of the peculiar style of art ornamentation, specimens of which are still extant in Irish manuscripts, and which was long erroneously assigned to the Anglo-Saxons, who now appear to have been indebted to the Irish mainly for Christianity, and entirely for letters. Among the eminent native Irish of these times were Columba (q.v.), or Cohim Cille, founder of the celebrated monastery of Iona; Comgall, who established the convent of Bangor, in the county of Down; Ciaran of Clonmacnoise; and Adamnan. abbot of Iona, and biographer of Columba. Of the Irish missionaries to the continent, the more distinguished were Columbanns (q.v.), founder of Bobio; Gallus of St. Gall, in Switzerland; DichM11, patronized by Clotdire; and Ferghal. or Virgilins, the evangelizer of Carinthia. The progress of Irish civilization was checked by the incursion of the Scandinavians, com mencing towards the close of the 8th and continued for upwards of 300 years.
Establishing themselves in towns on the eastern coast of Ireland, with the assistance of friendly native tribes, they continued to make predatory expeditious into the interior until their signal overthrow at the battle of Clonta.rf, near Dublin (1014 A.D.), by Brian, surnamed Borumha, monarch of Ireland. From the close of the 8th to the 12th Ireland, although harassed by the Scandinavians, produced many writers of merit, among whom were ..tEngus, the hagiographer; Corinne MacCullenan, king of Munster, and bishop of Cashel, the reputed author of Cormac's Glossary; Cuan O'Loehain; Gilts Moduda; Flan of Monasterboice; and Tighernach, the annalist. The Irish scholars who during these times acquired highest eminence on the continent were Joannes Erigtma, the favorite of Charles the bald of France; Dungal, one of the astronomers consulted by Charlemagne; Diclruill, the geographer; Douogh, or Donatus, bishop of Fiesole; and 3larianus Scotus. Of the state of the arts in Ireland during the same period, elaborate specimens survive in the shrine of St. Patrick's bell, the cross of Coug, in Mayo (12411 c.); the Limerick and Cashel croziers, and the Tara brooch, all displaying minute skill and peculiar style. To much earlier times is assigned the Book of Yells (see KEELS), a Latin copy of the four gospels, in the library of Trinity college, Dublin, which Mr. Westwood has pronounced to be the most elaberately executed manuscript of early art now in existence, and of portions of which facsimiles are given in his work Palavyraphia Sacra Pictoria. Of the Irish architecture of the period examples survive at Cashel. The well known round towers of Ireland are believed to have been erected about this era as belfries, and to serve as places of security for ecclesiastics duriug disturbances. The skill of the Irish musicians in the 12th c. is attested by the onthusiastie encomiums bestowed by Giraldus Cambrensis upon their perform ances. The Scandinavians have left behind them in Ireland no traces of civilization except coins struck at Dublin, Waterford, and Limerick, in which towns they were, for the most part, subject and tributary to the natives.
The first step towards an Anglo-Norman descent upon Ireland was made by Henry II., who obtained in 1155 a bull Iron pope Adrian IV., authorizing him to take posses sion of the island, on condition of paying to the papal treasury a stipulated annual revenue. Political circumstances prevented Henry from entering upon the undertaking till 1166, when Dermot] MaeMurragh, the deposed king of Leinster, repaired to him, and obtained authority to enlist such of his subjects as might be induced to aid hint in attempting to regain his forfeited lands. Dermot], returning to Ireland in 1169, with the aid of his foreign mercenaries, and still more numerous Irish allies, succeeded iu recovering part of his former territories, and in capturing Dublin and other towns on the eastern coast. After his death in 1171 the succession to the kingdom of Leinstcr was claimed by his son-in-law, Richard FitzGislebert, earl of Pembroke, surnamed "Strongbow." In the following year king Henry, with a formidable armament, visited Ireland, received homage from several of the minor native chiefs, and from the chief adventurers, granting to the latter charters authorizing them, as his subjects, to take possession of the entire island, in virtue of the grant made to him by the pope.. The chief Anglo-Norman adventurers, FitzGislebert, Le Gros, De Cogan, De Lacy, anti De Curei, encountered formidable opposition before they succeeded in establishing themselves on the lands which they thus clammed. The government was committed to a viceroy, and the Norman legal system was introduced into such parts of the island as were reduced to obedience to England. The youthful prince John was sent by king Henry into Ireland in 1184; but the injudicious conduct of his council having excite disturbances, he was soon recalled to England. John, when king, ma-de an expedition into Ireland in 1210, to curb the refractory spirit of his barons, who had become for midable through their alliances with the natives. During the 13th c. the principal Anglo-Norman adventurers succeeded in establishing themselves, with the feudal insti tutions of their nation, in some parts of Ireland, by the assistance or suppression ot native clans. .The Fitzgeralds, or Geraldines, acquired almost unbounded power in Kildare, and east Munster, or Desmond; the Le Botillers, or Butlers, in Ormond or west Munster; and Ike De Burghs, or Burkes, in Connaught. After the battle of Bannockburn, time native Irish of the north invited over Edward Bruce, and attempted to overthrow the English power in Ireland. The court of Rome, at the instigation of England, excommunicated Bruce with his Irish allies; but although his enterprise failed of success, the general result was a comparative collapse of the English dominion in Ireland. The descendants of the most powerful settlers gradually became identified with the natives, whose language, habits, and laws they adopted to so great an extent, that the Anglo-Irish parliament passed, in 1367, the "statute of Kilkenny," decreeing excommunication and heavy penalties against till those who followed time customs of, or allied themselves with, time native Irish. This statute, however, remained inoperative; and although Richard II., later in the 14th c., made expeditions into Ireland with large forces, he failed to effect any practical result; and the power and influence of the natives increased so much that the authority of the English crown became limited to a. few towns on the coast, and the district termed "the Pale," comprising a small circuit about Dublin and Drogheda.