In Greek mythology
referred to two different people
- King of Megara With the aid of Apollo, Alcathous rebuilt the walls of Megara, for which Megareus, gave him his daughter, Periboea, as a wife.
- King of Onchestus in Boeotia, father of Hippomenes. He was part of the Seven Against Thebes and committed suicide in response to a claim by the oracle Tiresias that Thebes would win if one person would voluntarily die to save it.