Donnchadh, son of Brian Boraimhe, held the sovereignty of Leath Mogha and the greater part of Ireland fifty years according to Finghin Mac Carrthaigh, in the booklet he has written on the History of Ireland, and others learned in the seanchus; and I think this opinion is more likely to be true than the opinion of those who say that Donnchadh reigned only twelve years. For Finghin's opinion is in accordance with the number of years that are from the death of Brian to the Norman Invasion, while the latter opinion is not. Hence I think that Finghin's opinion is the true one, which says that fifty years was the length of Donnchadh's reign. It was in the reign of Donnchadh that Harolt Conan, prince of Wales, fled to Ireland where he found shelter in the year of the Lord 1050. It was in Donnchadh's time that the following events took place. For it was then that Mathghamhain O Riagain, king of Breagha, took captive Amhlaoibh, son of Sitric, leader of the Lochlonnaigh in Ireland, and got a ransom of twelve hundred cows and six score steeds on his account.
It was about this time, also, that Flaithbheartach O Neill went on a pilgrimage to Rome the year of the Lord then being 1073. After this Tadhg, son of Lorcan, king of Ui Cinnsealaigh, died at Gleann da Loch while he was there as a penitent; and Gormfhlaith, daughter of Murchadh son of Flann king of Leinster, mother of Sitric, son of Amhlaoibh, leader of the Lochlonnaigh of Ireland, died, and she was the mother of Donnchadh, son of Brian Boraimhe. It was about this time that Cluain Fearta Breanainn was plundered by Art Coileach O Ruairc, king of Breithfne; and on the same day, Donnchadh, son of Brian, came upon him and made dreadful slaughter of his people in vengeance for that sacrilege they had committed. Soon after this, Cathal, son of Ruaidhri, king of west Connaught, went on a pilgrimage to Ard Macha. After this, Port Lairge was plundered and burned by Diarmaid son of Maol na mBo, king of Leinster, and Cluain Mic Nois was plundered by the Conmhaicne; and God and Ciaran avenged this on them, that is, most of their people and their cattle died soon afterwards.
It was about this time that Carrthach, son of Saoirbhreathach, king of Eoghanacht Chaisil, was burned, together with many other nobles, in a fire-house by the son of Longargan, son of Donn Cuan. After this Donnchadh, son of Brian, was deposed from his sovereignty, and went on a pilgrimage to Rome, where he died in the monastery of St. Stephen. And as to what many assert that the Pueraigh Eustasaigh and the Pluingceadaigh are descended from Donnchadh, I have found neither lay nor letter to prove that any of them were descended from him, except one stanza which is in the poem beginning: I will confer a favour on the clann Tail, which Maoilin Og Mac Bruaideadha a contemporary of our own has composed. Moreover as to the tradition that exists among many of the rustics who say that when Donnchadh went on a pilgrimage to Rome he had intercourse with the daughter of the emperor who was there then, and that she bore him a son, and that from that son might have sprung the three septs we have mentioned; this story cannot be true, for before setting out on that expedition he was a very old decrepid man of over eighty years of age, and it is not likely that an emperor's daughter would covet intercourse with such a veteran, and, moreover, it would have been unbecoming in him who went for the sake of pilgrimage and penance to covet any woman whatever.
And from what I have said, I judge that Donnchadh did not have intercourse with the emperor's daughter, and that she did not bear him a son from whom the septs referred to could have sprung.
The truth of this statement will be the more readily admitted as we read in an old book of annals, which was copied from the Speckled Book of Mac Aodhaghain about three hundred years ago, that Donnchadh, after having performed his pilgrimage to Rome, went to live in the monastery of St. Stephen in Rome, and that he took upon himself the yoke of piety, and passed the remainder of his life until death in penance in the same place.
We also read in the chronicles of the Normans, where the Norman nobles who came first to Ireland are enumerated, that it was at the beginning of the Norman Invasion that Robert le Power, from whom sprang the Pueraigh and the Eustasaigh in Ireland, first came, and the same authors say that the Pluingceadaigh are of Lochlonnach origin.
Toirrdhealbhach, son of Tadhg, son of Brian Boraimhe, held the sovereignty of Munster and of the greater part of all Ireland twelve years. Mor, daughter of Giolla Brighde O Maolmuaidh, king of Cineal Fiachaidh and and of Feara Ceall, was mother of this Toirdhealbhach O Briain. It was in his reign that the following events took place. For it was then that Conchubhar, son of Maoilseachlainn, king of Meath, was treacherously slain by his own brother's son, to wit, Murchadh, son of Flann, and his head was forcibly carried off from where he was buried at Cluain Mic Nois to Ceann Choradh by Toirrdhealbhach O Briain the Friday before Easter, and the same head was taken back northwards to Cluian Mic Nois the next Sunday, and this happened through the wonder-working of Ciaran.
It was in the reign of this Toirrdhealbhach that William Rufus, king of England, by the permission of Toirrdhealbhach O Briain, king of Ireland, sent to Ireland for timber with which to roof Westminster Hall in the year of the Lord 1098; and the year before that the first bishop, his name was Malcus, was consecrated at Port Lairge, by Anselmus, archbishop of Canterbury. It was about this time that Dearbhforgaill, daughter of Tadhg Mac Giolla Phadraig, wife of Toirrdhealbhach O Briain, king of the greater part of Ireland, died. After this Toirrdhealbhach O Briain, king of the greater part of all Ireland, died after he had reigned twelve years.
Muircheartach, son of Toirrdhealbhach, son of Tadhg, son of Brian Boraimhe, held the sovereignty of Leath Mogha and the greater part of all Ireland twenty years. Caileach Dhe, daughter of O Heidhin, was mother of Muircheartach O Briain and mother of Ruaidhri O Conchubhair. It was in his reign that the following events took place. In the first place it was he bestowed Cashel on the Church as an offering to God and to Patrick the first year of his reign, in the year of the Lord 1106; and about this time there was a general assembly of the men of Ireland, both lay and cleric, around Muircheartach O Briain, king of Leath Mogha in Fiadh Mic Aonghusa. Here follows the number of clerics that were at this assembly, namely, Maolmuire O Dunain, archbishop of Munster, and Ceallach son of Aodh, comhorba of Patrick, that is the vicar-general of the primate, and eight bishops, three hundred and sixty priests and seven score deacons, and many clerics that are not enumerated here. And they made regulations and laws and customs for the Church and the laity. After this, Maolmuire O Dunain, archbishop of Munster, died.