Born: 1953 August 22 in London, England, United Kingdom
Died: 2022 month? day? in United Kingdom?
Biography: Additional biographical information can be found in The Comics Journal (Fantagraphics, 1977 Series) #122 (June 1988).
O'Neill was the co-creator with Pat Mills of A.B.C. Warriors, Marshal Law, Metalzoic, Nemesis the Warlock, and Ro-Buster. He co-created the League of Extraordinary Gentlemen with Alan Moore.