Gaelic: Eochaid mac Run,
also written Eouchu or Eochaidh
Gaelic: Girc mac Dungail
Eochaid was descended from the female Side of the royal Family and therefore had -under the Law of Alba- no legitimate claim to the Throne, yet he had conspired with Giric against Aed to set the Crown together.
Their relationship to each other was marked by Hatred and Rivalry.
So it is not surprising that Eochaid tried to eliminate Griric with Donald -Son of Kenneth I. He also succeeded in a ‘Battle in Dundrun’ in 889, but was then displaced by Donald and exiled.