List of Famous people with last name O-neill

Art Oge O'Neill was a member of the O'Neill Dynasty of Tír Eoghain, Ulster, in medieval Ireland during the early Tudor era. In 1513 he became head of the O'Neills, holding the position until 1519 when he was succeeded by his half-brother.

Conn O'Neill was a member of the O'Neill dynasty, the most powerful Gaelic family in Ireland. He was the youngest son of Hugh O'Neill, Earl of Tyrone who had initially been a supporter of the Crown but led Tyrone's Rebellion between 1594–1603. He then made peace and was restored to royal favour following the Treaty of Mellifont. Conn's mother was Catherine O'Neill, Countess of Tyrone, from the Magennis family of Iveagh.

Sir Turlough MacShane O'Neill was an Irish landowner. He was part of the powerful Gaelic O'Neill Dynasty of Ulster. He was a great grandson of Shane O'Neill, who had once been chief of the O'Neills before his death in 1567. Turlough's branch of the family had served on the Crown's side against their cousin Hugh, Earl of Tyrone, during Tyrone's Rebellion (1594-1603). They were rewarded with land around Kinnaird in County Tyrone.