Denis Armar O'Conor Don, (1912–10 July 2000) was hereditary chief of the O'Conor Don

O'Conor Don

The Ó Conchubhair Donn is the hereditary Prince and Chief of the Name of the Royal Family of Connacht, the Clan Ó Conchubhair.-Overview:...

 sept of Ireland

Ireland

Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...

.

Born in London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

 in 1912 to Charles William O'Conor and Evelyn Lowry-Corry, he inherited his title in 1981 from his second cousin Fr. Charles O'Conor, a Jesuit priest. He used his position to promote an interest in Irish heritage from genealogy, local history to archaeology. He became President of the Dún Laoghaire

Dún Laoghaire

Dún Laoghaire or Dún Laoire , sometimes anglicised as "Dunleary" , is a suburban seaside town in County Dublin, Ireland, about twelve kilometres south of Dublin city centre. It is the county town of Dun Laoghaire-Rathdown County and a major port of entry from Great Britain...

 Genealogical Society in 1991 and President of the Genealogical Society of Ireland

Genealogical Society of Ireland

Genealogical Society of Ireland is a voluntary non-governmental organisation promoting the study of genealogy, heraldry, vexillology and social history in Ireland and amongst the Irish Diaspora as open access educational leisure pursuits available to all...

in 1999.

He married Elizabeth Marris and they had a son, Desmond. With his second wife, Rosemay (née O'Connell Hewett), he had two sons: Kieran and Rory. A daughter, Gail, died aged thirteen.

His eldest son, Desmond, inherited his title of O'Conor Don.