In the fourth century before Christ the three Collas play a great part in the mythic history of Ireland, and are likewise connected with a supposed settlement in Scotland. Cormac, the son of Aet, and grandson of Conn of the hundred battles, whom we have already adverted to, has a son, Cairbre Liffechair, so called from the river Liffey near which he was nursed, who likewise becomes _Ardri_ of Erinn. He has two sons, Fiacha Sraibtaine and Eochaidh Doimlein. The former marries Aeifi, daughter of the king of the Gallgael, and was the father of Muredach Tirech, from whom the subsequent kings of Ireland of the race of Niall derived their descent. The latter marries Oilich, daughter of the king of Alban, called by some Vadoig, by others Uigari, and has three sons, Caerill, Muredach, and Aedh. These take the name of Colla, and are called respectively Colla Meann, Colla da Crioch, and Colla Uais. These Collas slay their uncle Fiacha, and Colla Uais becomes king of Ireland, but is driven from thence with his brothers in 326 by Muredach Tirech, and takes refuge with his paternal grandfather the king of Alban, from whom he receives _Buannacht_ or military maintenance. Three hundred warriors were his host. After remaining three years in Alban the three brothers return to Erinn, each with a following of nine warriors, and having been reconciled with Muredach Tirech, who tells them they ought to conquer some territory as an inheritance, they are joined by seven ‘catha’ or battalions of the Firbolg of Connaught, and with their assistance attack the king of Ulster, march to the Carn of Achadhleithderg, from whence they fought seven battles, one on each day of the week, and on the last slay the king of Ulster, plunder and burn his capital, of Emania, and acquire a large territory as their swordland, which was termed Oirgialla, and was possessed by their descendants. This is the story of the three Collas, and in this manner the great Pictish kingdom, of which Emania was the capital, was supposed to come to an end in the year 331, and the Cruithnigh of Ulster confined to the district of Dalaradia on the east coast of Ulster. From Colla Uais the Sennachies both of Erinn and Alban deduced the descent of Somerled, who became the Regulus of Arregaidhel and of half of the Western Isles, and from whom sprang the potent clan of the MacDougalls, Lords of Lorne, and the MacDonalds, Lords of the Isles.[131] [Sidenote: The last three pagan kings of Ireland in Scotland.]