Irish derivation: Ó Néill.

Name meaning: "Descendant of Niall."

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

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

Read more: What's your Irish clan?

Interesting Facts:

- 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.

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Some famous O’Neills:

- 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)

- Congress Thomas 'Tipp' O'Neill (1912-1994, a US Speaker of the House of Representatives and an advocate of the Irish cause)

Read more: What's your Irish clan?