O'Conor (Middle Irish: Ó Conċuḃair; Modern Irish: Ó Conċúir, often Anglicized as O'Connor), is an Irish princely and noble family of Gaelic origin who are the historic Kings of Connacht and the last High Kings of Ireland before the Norman invasion. The family seat is Clonalis House outside Castlerea in County Roscommon.
The O'Connor family can trace their lineage back to the 5th century without dispute. Many ancient records suggest they descend from the Milesian kings, whose pedigree ultimately leads to Japheth the son of Noah, ten generations off the Biblical Adam.
The clan name originated in the 10th century as a derivative of its founder Conchobar mac Taidg Mór. The family contributed to Irish society in art, history, language, politics, diplomacy, etc... before, during and after foreign rule in Ireland. They descend in the paternal line from the Connachta's Uí Briúin Ai. The current O'Connor Don is Desmond O'Connor Don (b. 22 September 1938) who lives in Rotherfield, East Sussex in England.
The Ó Conchubhair Donn is the senior head of a lineage which provided about one hundred Kings of Connacht, thirty Chief of the Name and two High Kings of Ireland, Tairrdelbach Ua Conchobair (1088–1156), and his son Ruaidrí Ua Conchobair (c. 1115–1198).
During the late 14th century, the Ó Conchubhair dynasty grouped into two main divisions, one led by Toirdealbhach Ruadh, the other by Toirdealbhach Óg (also called Toirdealbhach Donn), both in the seventh generation of descent from Cathal Crobhderg. From these descended the families of Ó Conchubhair Ruadh (now extinct) and Ó Conchubhair Donn.
Ireland's pre-eminent 19th-century historian, John O'Donovan, once said of the O'Conor's "No family in Ireland claims greater antiquity and no family in Europe, royal or noble, can trace its descent through so many generations of legitimate ancestors."[full citation needed] The O'Conor name has produced many other surnames, some of which are O'Connor, Connor, Conner, Conners, Connors. People of all of these names may still descend from Ruaidrí Ua Conchobair, but many would descend from other O'Connor sects such as O'Connor offaly or O'Connor Kerry.
On the death in 1981 of Rev. Charles O'Conor Don SJ, Clonalis House, the ancestral seat of the O'Conor Don Family, passed to his sister Gertrude O'Conor Nash. Consequently, not for the first time, the family title and family seat were separated, remaining within a more direct O'Conor family lineage.
The O'Conor Nash family now reside at Clonalis House where they maintain the O'Conor archives.
Kings of Connacht