Fiacha mac Delbaíth

In the medieval Irish regnal and mytho-historical compilations, Fiacha mac Delbaíth is presented as son of Delbáeth and member of the Tuatha Dé Danann who succeeded his father as High King of Ireland. Different sources record variants of his accession—some accounts indicate he took the kingship after his father was overthrown by another, while annalistic traditions (and later summaries) present him as having overthrown or killed his father to claim the crown. He is incorporated into the sequence of legendary rulers used by compilers to narrate Ireland's prehistory.

The supplied sources offer no physical or iconographic description of Fiacha. He is attested only in genealogical, regnal, and battle-list contexts; no bodily attributes or costume details are recorded in the provided passages.

The texts attribute political and martial agency to Fiacha: accession to the High Kingship, a recorded reign of ten years, and participation in the major battle narratives of the Tuatha Dé Danann. He is described as having fallen in battle (listed among the Tuatha's casualties in Cath Maige Tuired and the Lebor Gabála), and some traditions report patricide as the means of his accession. No explicit supernatural powers or magical feats are attested in the provided materials.