After the death of Muirkertagh ” of the Leather Cloaks,” the Norse power in Ireland was considerably strengthened, and in the beginning of the second half of the tenth century it was as full as at any time since Turgesius. Domhnall O Neill* son of Muirkertagh, who became Ard Ri in 956, was mostly engaged in conflict not only with the Southern Ui Neili and Laighin, but even with Connacht, whose King was reviving the claims of the Western Siol Ch.tinn to supreme power. Consequently he was unable to curb the Norse settlers, who, despite their recent conversion, continued to raid the country.

Two great warriors were now, however, coming forward, one in Munster, the other in Meath, whose united efforts were to dispel at last the menace of the Norsemen.

It has been observed that of the two families who were entitled to reign over Munster, the Eoghanacht, or Southern, family had long monopolised the throne. The Dal Chais, however, were now asserting themselves, and in the year 964 their chief Mahon became King ” in Caiseal.” At that time the Norse of Limerick held nearly all the south in subjection. Mahon for a time fought against them vigorously, but at length made peace. But his younger brother, the famous Brian Boroimhe, refused to have any truce with the foreigners and retired to the fastnesses of Slieve Aughty on the Connacht borders where, with a small body of followers, he kept up a relentless guerilla warfare.

Above: St. Laurence O’Toole

In the early part of this period the condition of the Church, and the state of religion generally present a sad contrast to the glories of the period before the coming of the Norsemen. The continued warfare had played havoc with the Church, and had, to a great extent, demoralised the people. The persistent manner in which the Norse had singled out churches and monasteries for their attacks had left many of the sanctuaries deserted, and many districts deprived of the exercise of religion. Not a few of the Irish chiefs, unfortunately, followed the example of the invaders, and displayed the loss of the old reverence by frequent attacks on some of the most venerated monasteries, by appropriating the church lands, and by claiming the right, frequently asserted by force, of imposing their own nominees upon Church offices. The corruption of manners is also illustrated by frequent breaches of faith and acts of cruelty.

Brian Boru the son of Kennedy, of the Dalgas race (157) was born in Kincora in 941. In 964 his brother Mahon became king of all Munster. At this time the Danes held the chief fortresses of the province, including Limerick, Cork, and Waterford, from which their marauding parties swept continually over the country, murdering and destroying wherever they came. King Mahon and his brother Brian, finding that they were not strong enough to withstand them openly, crossed the Shannon with those of their people who abode on the open plains, and took refuge among the forests and mountain solitudes of Clare. From these retreats thev carried on a relentless desultory warfare with tlie foreigners, during which no quarter was given on either side.

After a. tune both parties grew tired of these destructive conflicts, and a truce was agreed on between Mahon and the Danish leaders. But young Brian would have no truce : and he maintained the war on his own account against fearful odds, till at last he was left with only fifteen followers. And now the king, Mahon, hearing how matters stood, and fearing for his brother’s safety, visited him in his wild retreat, and tried to persuade him to abandon further resistance as hopeless. But all in vain : the young chief was not. to be moved from his purpose. And he at length persuaded his brother the king to resume hostilities ; and the two brave brothers collecting all their forces formed an encampment at Cashel, from which they sent expeditions to ravage the Danish settlements all round.

Now when Ivar of Limerick, king of the Munster Danes, heard of this uprising, he was infuriated to madness; and making- a mighty gathering of all the Danes of Munster he determined to march into Thomond and exterminate the whole Dalcassian race root and branch. Molloy king of Desmond and Donovan king of Hy Carbery (in the present Co. Limerick) basely joined and encouraged him; and bent on vengeance he set out from Limerick with his whole army for the encampment at Cashel.