invaded Munster and made peace for a year at Tullagh O'Dea, co. Clare. He came home through Connaught. His last expedition was in 1120, when he marched to Athlone to support Murchadh O'Maeleachlainn, who was attacked by the king of Connaught. He died at Derry on 9 Feb. 1121. He is praised for his fine physical form by the Ulster chroniclers, and for his virtues; but, except some traces of religious feeling shown in his relations towards two archbishops of Armagh, nothing but acts of unrelenting warfare are recorded of him. He married Bebhinn, daughter of Cenneidigh O'Brien, in 1090, and had by her two sons —Muircheartach, who died in 1114, and Niall, who died in 1119. She died in 1110.
[O'Donovan's edition of Annala Rioghachta Eireann, Dublin, 1851, vol. ii.; Colgan's Acta Sanctorum Hiberniæ, Louvain, 1650; Clarendon MS. xlv. in British Museum.]
O'LOCHLAINN, MUIRCHEARTACH (d. 1166), king of Ireland, son of Niall O'Lochlainn, son of Domhnall O'Lochlainn [q. v.], chief of the Cinel Eoghain, was ninth in descent from Domhnall, brother of Niall (870?–919) [q. v.], king of Ireland, from whom, and not from their more remote ancestor, Niall Naighiallach, the O'Neills take their name, according to O'Donovan. His family, who in later times were more often called MacLochlainn, were the senior branch of the Cinel Eoghain, the descendants of Eogfaan, son of Niall Naighiallach. He first appears in the chronicles in 1139, when he defeated the Clann Laithbheartaigh or O'Dubhdas of Ulster, and slew their chief, Mathghamhain. In 1142 he won a battle over the O'Donnellys, a sept of the Cinel Eoghain, in which he received a severe wound. The chiefship of the Cinel Eoghain was assumed in 1143 by Domhnall O'Gairmleadhaigh, the tribe having expelled Muircheartach. He went to the Cinel Conaill, and, with their aid, displaced O'Gairmleadhaigh, and was established as chief of Cinel Eoghain. Cu Uladh MacDuinnsleibhe, king of Ulidia or Lesser Ulster, made a foray in 1147 into Farney, co. Monaghan. Muircheartach O'Neill led the Cinel Eoghain, in alliance with Donnchadh O'Cearbhaill and the Oirghialla, and attacked the Ulidians, whom they found at Uchdearc, co. Down, drove before them to Dundrum, co. Down, and routed in a battle fought on the feast of SS. Peter and Paul, returning with much plunder to Tyrone. He again invaded Ulidia in 1148, and took hostages; but the Oirghiulla, who had marched with him, unexpectedly joined the Ulidians, and he had to retreat. He soon returned, crossing the Ban at Toome Bridge, deposed Culladh, and set up Donnchadh MacDuinnsleibhe as king of Ulidia. Later in the year he attended a convention of the chiefs of the Cinel Eoghain, the Oirghialla, and the Ulidians, who all swore to preserve general peace on a famous relic — the crozier known as the 'bachall iosa' — in the presence of Gilla MacLiag, archbishop of Armagh. The Oirghialla, Cinel Conaill, and Ulidians, all gave him hostages at this time. War, however, broke out in 1149, and he again invaded Ulidia and took many cattle, and received the king's son as a hostage. He went on with all his horsemen to Louth, and there received hostages sent by Tigheaman O'Rourke from Breifne. He next marched to Dublin, and received the submission of the Danes and hostages from Diarmaid MacMurchadha, king of Leinster. In 1150 he gave a gold ring of five ounces and other gifts to Flaibheartach O'Brolchain [q. v.], coarb of Columba, and permitted a general taxation of Cinel Eoghain for the wants of the church of Derry. He marched to Inismochta in Meath, and there received hostages sent to indicate the acknowledgment of his supremacy by Connaught, afterwards going on to Dunlochad, near Tara, where he ratified a treaty of peace with the foreigners of Dublin and Fingall. Turlough O'Brien and Turlough O'Connor [q. v.] were engaged in war, and the Munstermen, under the termer, suffered a disastrous defeat at Moinmor in Munster in 1151. Oljochlainn, taking advantage of this, led the Cinel Eoghain, Cinel Conaill, and Oirghialla across the Erne at Assaroe, co. Donegal, to the Curlew Mountains. Turlough O'Connor, unable to resist such an attack after his long fighting with O'Brien, sent hostages. Next year O'Lochlainn expelled Donnchadh O'Cearbhaill from the kingship of the Oirghialla, in revenge for an insult to the Archbishop of Armagh. He met Turlough O'Connor at the Moy near Ballyshannon, co. Donegal, where they declared amity on the bachall iosa and some relics of St. Columba. They afterwards met at Rathkenny in Meath, and Diarmaid MacMurchadha also came to the meeting. They deprived Tigheaman O'Rourke of Conmhaicne, a country consisting of Longford and the southern part of Leitrim, and divided Meath into east and west, giving the west to Murchadh O'Maeleachlainn, and East Meath to his son Maeleachlainn O'Maeleachlainn. In 1153 he decided to try and restore Turlough O'Brien, and marched to Creeve, co. Westmeath. Tadhg O'Brien, who had displaced Turlough O'Brien, marched thither to attack him, and Turlough O'Connor
