Makbar, Cardassian Chief Archon in 2370
Archon is the title given to a high magistrate or ruler. No being has yet been called simply an "archon"; the lead magistrate on Cardassia Prime is given the title of Chief Archon (DS9: "Tribunal"), while the title of Supreme Archon was given to the leader of the fictitious R'kaal race. (VOY: "Renaissance Man")
Supreme Archon Loth of the R'kaal