Dictionary of National Biography, 1885-1900/O'Rourke, Tiernan
O'ROURKE, TIERNAN (d. 1172), king of Breifne, called in Irish Tighearnan Ua Ruairc, was head of the clans known as the Ui Briuin, or as the race of Aedh finn, and ruled Breifne, called in English state papers ‘the Breny,’ a district including the modern counties of Leitrim and Cavan; and Conmaicne, which corresponds to the county of Longford. He first appears in the chronicles in 1124, and at that date had a son, Gillabroide, who was slain in battle with the Connaughtmen. O'Rourke had a considerable body of cavalry, and was defeated by a similar force under Conchobhar MacLochlainn at Ardee, co. Louth, in 1128. In 1130 he defeated and slew Diarmait O'Maelsechlainn, king of Meath, at Slieve Guaire, co. Cavan, and in the following year he ravaged Cuailgne and Omeath, then districts of Ulster, now in the co. Louth. He fought the Connaughtmen in 1132, in 1133 made an incursion into Fermanagh, and in 1137 and 1139 invaded Meath. He was expelled from the chiefship of the Ui Briuin by the clan in 1141, after an unsuccessful war with the O'Connors, but regained his position before the end of the year, and in 1144 obtained half Meath from Turlough O'Connor [q. v.] In 1145 he attacked O'Connor, and again in 1146; and in 1148 invaded Ulidia with Donnchadh O'Carroll. Later in the year he was himself wounded when on his way to meet the king of Connaught. He gave hostages to Niall O'Lochlainn in 1149, and in 1150 was confirmed in possession of part of Meath by Muircheartach O'Lochlainn [q. v.] In 1152 Conmaicne was taken from him by MacLochlainn, and O'Connor and Diarmait MacMurchadha carried off his wife Dearbhforgaill, with all her cattle and movable possessions. She was forty-four years of age, and there seem very slight grounds for the current story that this elopement had anything to do with the Norman invasion of Ireland eighteen years later. She was daughter of Murchadh O'Maeleachlainn, and died at Mellifont Abbey, near Drogheda, in 1193. He had another war with Connaught in 1158, but made peace in 1159, and fought Muircheartach O'Lochlainn, but was routed at Ardee by the Ulstermen. He continued in alliance with Connaught for several years afterwards. In 1162 his son Maelseachlainn was slain by one of his own clan. Diarmait MacMurchadha paid him one hundred ounces of gold as a reparation in 1167, while Dearbhforgaill built a church at Clonmacnoise. He obtained eight hundred cows as an eric from the Meathmen for the murder of O'Fionnallain, for whom he was security. He was slain at Tlachta, co. Meath, by Hugo de Lacy in 1172, and his body was decapitated. His head was fixed on a gate of Dublin, and his body hung by the feet from a gibbet on the north side of the city.
Nineteen other chiefs or tanists named Tiernan O'Rourke occur in the Irish chronicles, of whom the most important was chief of the race of Aedh finn and of Breifne, married Aine, daughter of Tadhg MacDonnchaidh, and died in 1467.
[Annala Rioghachta Eireann, vols. ii. iii.; Book of Fenagh, ed. Hennessy; Annals of Loch Cé, ed. Hennessy, Rolls Ser.]