Show ContentsO'Conor History, Family Crest & Coats of Arms

Etymology of O'Conor

What does the name O'Conor mean?

Today's Irish surnames are underpinned by a multitude of rich histories. The name O'Conor originally appeared in Gaelic as Ó Conchobhair, derived from the personal name Conchobhar. 1

Early Origins of the O'Conor family

The surname O'Conor was first found in Connacht. There were six different septs of this famous name scattered throughout Ireland, of which four continue to boast many members. However, the most important O'Connors were those of Connacht, divided into three main branches: O'Conor Don; O'Conor Roe; and O'Conor Sligo.

The Connacht O'Connors were direct descendants of Conchobhar, King of Connacht, who died in 971 AD. Furthermore, this family produced the last two High Kings of Ireland: Turlough O'Connor (1088-1156) and Roderick O'Connor (1116-1196). It was the invasion of Leinster by Roderick O'Conner on behalf of the Prince of West Brefney that caused the King of Leinster, Dermod MacMorough, to flee to England for aid. This resulted in the Strongbow Invasion of 1168, the beginning of English domination over Ireland.

Despite remaining stubbornly Catholic, the O'Connor family continued to maintain their elite position among the Irish nobility throughout the entire period of British dominance.

Early History of the O'Conor family

This web page shows only a small excerpt of our O'Conor research. Another 182 words (13 lines of text) covering the years 1002, 1641, 1652, 1666, 1698, 1710, 1763, 1791, 1838, 1852 and 1906 are included under the topic Early O'Conor History in all our PDF Extended History products and printed products wherever possible.

O'Conor Spelling Variations

Irish names were rarely spelled consistently in the Middle Ages. Spelling variations of the name O'Conor dating from that time include Connor, Conner, Conor, Connors, O'Connor, Connores, Conner, Connar, Connars, O'Connar, O'Conner, Connair, Connairs, Connaire, Connaires, Cawner, Cawners, Caunnor, Cauner, Cauners and many more.

Early Notables of the O'Conor family

Notable amongst the family name at this time was

  • Cabrach O'Conor and Hugh O'Connor, son and grandson of O'Conor Don, took a prominent part in the 1641-1652 wars
  • Charles O'Conor (1710-1791), was Collector of Irish manuscripts; Charles Owen O'Connor (1838-1906), President of the Royal Irish Academy; and Arthur O'Connor (1763-1852), was an United Irishman and ge...

Migration of the O'Conor family

Thousands of Irish families left for North American shores in the 19th century. These people were searching for a life unencumbered with poverty, hunger, and racial discrimination. Many arrived to eventually find such conditions, but many others simply did not arrive: victims of the diseased, overcrowded ships in which they traveled to the New World. Those who lived to see North American shores were instrumental in the development of the growing nations of Canada and the United States. A thorough examination of passenger and immigration lists has disclosed evidence of many early immigrants of the name O'Conor: William Conner who settled in Plymouth, arriving on the "Fortune" in 1621; just a year after the "Mayflower," Cornelious Conner, who settled in Exeter in 1650.


Contemporary Notables of the name O'Conor (post 1700) +

  • Charles O'Conor (1804-1884), American lawyer and politician, a candidate in the 1872 U.S. presidential election
  • Herbert Romulus O'Conor (1896-1960), American Democratic Party politician, the 51st Governor of Maryland (1939-1947)
  • Charles O'Conor (1764-1828), Irish priest and historical author
  • Eugene Joseph O'Conor (1835-1912), Irish-born, New Zealand Member of Parliament
  • Denis Maurice O'Conor (1840-1883), Irish politician, Member of Parliament, High Sheriff of Roscommon in 1865
  • Matthew O'Conor (1773-1844), Don of Ballinagare, County Roscommon, Irish historian, the O'Conor Don and de jure King of Connacht
  • Denis O'Conor (1794-1847), the O'Conor Don, Irish nobleman and politician, Member of Parliament for Roscommon (1831-1847), Junior Lord of the Treasury (1846-1847)
  • Charles Owen O'Conor PC (1838-1906), the O'Conor Don, Irish Member of Parliament for Roscommon (1860–1880), Lord Lieutenant of Roscommon (1896–1906)
  • Roderic O'Conor (1860-1940), Irish painter and etcher from Milltown, Castleplunket, County Roscommon
  • John O'Conor (b. 1947), Irish pianist and pedagogue, former director of the Royal Irish Academy of Music, recipient of an Honorary Fellowship by the Royal Irish Academy of Music
  • ... (Another 4 notables are available in all our PDF Extended History products and printed products wherever possible.)


The O'Conor Motto +

The motto was originally a war cry or slogan. Mottoes first began to be shown with arms in the 14th and 15th centuries, but were not in general use until the 17th century. Thus the oldest coats of arms generally do not include a motto. Mottoes seldom form part of the grant of arms: Under most heraldic authorities, a motto is an optional component of the coat of arms, and can be added to or changed at will; many families have chosen not to display a motto.

Motto: O Dhia gach an cabhair
Motto Translation: From God Every Help


  1. MacLysaght, Edward, The Surnames of Ireland. Ireland: Irish Academic Press, sixth edition, 1985. Print. (ISBN 0-7165-2366-3)


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