Duach mac Dallán, 6th king of Uí Maine, fl. 5th-century/6th-century.
John O'Donovan remarked that "Dallan, who was also a brother of Fiachra Finn, was prince of Hy-Maine for eleven years, when he was mortally wounded and afterwards drowned."
References
Duach mac Dallán Wikipedia(Text) CC BY-SA