Madoc or Madog (Madoc ap Owain Gwynedd)(mădˈək, mäˈ–) [key], fl. 1170?, quasi-historical Welsh prince. According to Welsh legend, Madoc, said to be a son of Owain Gwynedd, discovered America 300 years before Columbus. Witnesses' accounts of finding supposedly Welsh-speaking Native Americans have served to keep alive the story, which is otherwise unsupported by evidence. He is the subject of Robert Southey's Madoc.