Fiacha (earlier Fíachu) is a name borne by numerous figures from Irish history and mythology, including:
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Fiacha Cennfinnán, High King of Ireland in the 16th or 20th century BC
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Fiacha mac Delbaíth, High King in the 14th or 18th century BC
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Fiacha Labhrainne, High King in the 11th or 15th century BC
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Fiacha Finscothach, High King in the 10th or 14th century BC
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Fiacha Finnailches, High King in the 9th or 13th century BC
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Fiacha Tolgrach, High King in the 6th or 9th century BC
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Fiacha Sraibhtine, High King in the 3rd century BC
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Fiacha Finnfolaidh, High King in the 1st century AD
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Fiacha Muilleathan, a king of Munster in the 3rd century AD
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Fiachu mac Néill, son of Niall of the Nine Hostages
Similar names
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Fiach
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Fiachra
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Fiachna
{{given name
Irish-language masculine given names