How Medb came to power in Connacht and married Ailill is told in the tale Cath Bóinde ("The Battle of the Boyne"), also known as Ferchuitred Medba ("Medb's man-share"). Her father, Eochu Feidlech, the High King of Ireland, married her to Conchobar mac Nessa, king of the Ulaid, because he had killed Conchobar's purported father, the former High King Fachtna Fáthach, in battle. She bore him a son, Glaisne, but the marriage was a bad one and she left him. Eochaid gave Conchobar another of his daughters, Eithne (or Clothru), but Medb murdered her while she was pregnant; her son Furbaide was born by posthumous caesarian section.