Everything you need to know about the Irish surname O'Neill.

Over 70 million people worldwide claim to have a link to Ireland through their ancestry. It's incredible to think of the power of the Irish diaspora and how many people right now are on their journey searching out information on their family name.

Do you have the Irish last name O'Neill, but know absolutely nothing about it? Here's everything you need to know from its meaning to some interesting facts about the Irish family name. 

Irish derivation: Ó Néill.

Name meaning: "Descendant of Niall."

Counties associated with the name: Tyrone, Derry, Donegal, Meath, Dublin, Carlow, Tipperary, and Wicklow.

Coat of arms motto: "The red hand of Ireland."

Interesting Facts about the surname O'Neill:

Thanks in part to the fleeing of Irish lords, many O'Neills can be found in places in Europe like Holland, Spain, and France, as well as the Caribbean.

The O'Neills can trace their family history back to A.D. 360, a rare feat among the families of Europe.

The O'Neills take their name from Niall Glúndub, an early 10th-century High King of Ireland from the Cenél nEógain. Cenél nEógain, descendants of Eógan mac Néill, were a branch of the Uí Néill dynasty who took their name from Niall of the Nine Hostages, a legendary 5th century King of Tara.

Famous people with the last name O'Neill:

  • Sir Niall O'Neill (1658-1690, who distinguished himself at the battle of the Boyne)
  • Arthur O'Neil (1737-1816, a blind harpist of great renown)
  • John O'Neill (1834-1878, a Fenian leader)
  • Eugene O'Neill (1888-1953, the dramatist, was the son of an American actor, himself an Irish immigrant)
  • Ed O'Neill (1946-, an Irish American actor)
  • Congress Thomas 'Tipp' O'Neill (1912-1994, a US Speaker of the House of Representatives and an advocate of the Irish cause)

* Originally published in 2011, updated in October 2022.

Do you know any O'Neills? Let us know in the comments!