Hugo José Jorge O'Neill (7 June 1874 in Lisbon, Santos-o-Velho – 30 March 1940 in Palmela) was the head of the O'Neill Clandeboy (Ó Néill Clann Aodha Buidhe) dynasty, which ruled a kingdom in Gaelic Ireland until the early 17th century, and has been in Portugal since the 18th century.
He was the first son of the previous head of the family of Jorge Torlades O'Neill II and wife Maria Isabel Mazziotti da Costa Cordeiro Fernandes.
Hugo José Jorge O'Neill was an Officer of the Portuguese Navy and an Officer at the Orders of Kings Carlos I of Portugal and Manuel II of Portugal.
[1] He met and corresponded with Roger Casement in 1904 (when Casement was briefly consul general in Lisbon) and the also met with the Belfast antiquarian solicitor Francis Joseph Bigger.
[citation needed] O'Neill also employed an Irish governess for his children.