Fothad Airgthech

Fothad Airgthech ("ingenious" or "plundering"), son of Lugaid mac Con, was joint High King of Ireland with his brother Fothad Cairpthech, reputedly in the 3rd century. They had ruled a year when Fothadh Airgthech killed his brother, and was himself killed by Caílte mac Rónáin of the fianna in the Battle of Ollarba.