Ó Seachnasaigh, O'Shaughnessy, collectively Uí Sheachnasaigh, clan name Cinél nAedha na hEchtghe, is a family surname of Irish origin. The name is found primarily in County Galway and County Limerick. Their name derives from Seachnasach mac Donnchadh, a 10th-century member of the Uí Fiachrach Aidhne, which the Ó Seachnasaigh were the senior clan of. The town of Gort, Ireland, was the main residence of the family since at least the time of their ancestor, King Guaire Aidne mac Colmáin.
Uí Fhiachrach Aidhne was a kingdom located in what is now the south of County Galway.
The O'Donovans are an Irish family. Their patronymic surname derives from Irish Ó Donnabháin, meaning the grandsons or descendants of Donnubán, referring to the 10th century ruler of the Uí Fidgenti, Donnubán mac Cathail. During the 12th and 13th century, O'Donovan relations relocated from the Bruree/Croom area south to the Kingdom of Desmond and to Carbery, where they were a ruling family for centuries and played a role in the establishment of a feudal society under the MacCarthys. Other septs retreated into the southeast corner of the Ui Fidgheinte territory, reaching from Broadford/Feenagh to the Doneraile area. The northern septs of the O'Donovans did not use a White Rod as the family's position in their original territory was vastly eroded, while several septs of O'Donovans in the southwest territories were semi-autonomous flatha under the MacCarthy Reagh dynasty in Carbery, with the most notable being local petty kings. The family were counted among the leading Gaelic nobility of Ireland.
The MacCarthy Reagh dynasty are a branch of the MacCarthy dynasty, Kings of Desmond, deriving from the Eóganacht Chaisil sept.
Cenél Áeda na hEchtge was a trícha cét (later a cantred, and which was the original formation of the southern part of the barony of Kiltartan, County Galway. This was the clan name of the O Shaughnessys and O Cahills who both ruled the territory until the O Cahills were forced from the area by the O Shaughnessys. The latter remained chiefs of the area until 1691 and the head family survived in the Gort area till the demise of the senior line in the 18th century. The name was taken after the cenél of Aedh, uncle to King Guaire Aidne mac Colmáin of Connacht.
William O'Shaughnessy, The O'Shaughnessy was an Irish Chief and Major-General.
Ruaidhrí Gilla Dubh Ó Seachnasaigh was an Irish Knight and Chief of the Name. He is known in English as Sir Roger O'Shaughnessy.
Síol Maelruain was a territory located in north County Roscommon due west, from what is now Castlerea. Its lake, Lough O'Flynn, is the source of the River Suck and is located at the foot of Slieve O'Flynn mountain. The lordship was centered on the village of Ballinalough, its rulers been the Ó Floinn family. David Flynn (chaplain) was Chaplain to James III.
Diarmaid Ó Seachnasaigh, Irish knight and Chief of the Name, died before 1567.
Diarmaid Riabach Ó Seachnasaigh, Chief of the Name, died 1579.
Sir Liam Ó Seachnasaigh was an Irish Chief of the Name.
Sir Dermot Ó Seachnasaigh, Chief of the Name, died 1606. He was a son of Sir Ruaidhrí Gilla Dubh Ó Seachnasaigh and Lady Honora O'Brien, daughter of Murrough O'Brien, 1st Earl of Thomond.
Sir Ruadhri Gilla Dubh Ó Seachnasaigh was Chief of the Name during 1583–1650.
Sir Dermott Ó Seachnasaigh, Chief of the Name, died 1673.
Roger O'Shaughnessey or O'Shaughnessy may refer to:
Gilla na Naemh Crom Ó Seachnasaigh was an Irish Chief of the Name.
Colman O'Shaughnessy, O.P. was an Irish Roman Catholic clergyman who served as Bishop of Ossory from 1736 until his death in 1748.
Carbery, or the Barony of Carbery, was once the largest barony in Ireland, and essentially a small, semi-independent kingdom on the southwestern coast of Munster, in what is now County Cork, from its founding in the 1230s by Donal Gott MacCarthy to its gradual decline in the late 16th and early 17th centuries. His descendants, the MacCarthy Reagh dynasty, were its ruling family. The kingdom officially ended in 1606 when Donal of the Pipes, 17th Prince of Carbery chose to surrender his territories to the Crown of England; but his descendants maintained their position in Carbery until the Cromwellian confiscations, following their participation in the Irish Rebellion of 1641 after which some emigrated to the Chesapeake Colonies.
John Ó Seachnasaigh was an Irish Chief of the Name.
