Flathghal mac Flannbhrath, King of Umaill, died 782. Flathghal's relationship to the previous two kings is unknown, as they does not seem to appear in the extant genealogies. However, he was a son of King Flannabhra (died 773) and was succeeded in 782 by his brother, Cosgrach mac Flannbhrath. The succession in these years may have been disputed between two or more different segments of the ruling dynasty before settling upon the sons of Flannabhra.