Fergus mac Roich

For other personages and places called Fergus, see Fergus. In Irish mythology, Fergus (or Fearghus) mac Róich (or mac Róeg) is the former king of Ulster during the events of the Ulster Cycle. He was tricked out of the kingship by Ness, who made her seven-year-old son Conchobar mac Nessa king in his place. T. F. O'Rahilly proposed that Fergus Foga was another name for Fergus mac Róich, and the literary character Fergus mac Léti may be another version of him.
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[Celtic] The heroic tutor of Cuchulainn, who left Conchobar's court after the treacherous murder of the sons of Usnech.