Sírna Sáeglach ("the long-lived"),[1] son of Dian mac Demal, son of Demal mac Rothechtaid, son of Rothechtaid mac Main, was, according to medieval Irish legend and historical tradition, a High King of Ireland.
He separated the province of Ulster from the authority of the High King, and is said to have made war against the Ulaid, who had killed his great grandfather, for a hundred years according to the Lebor Gabála Érenn,[2] 150 years according to the Annals of the Four Masters,[3] but Geoffrey Keating, citing an ancient poem, gives him only twenty-one years.
[4] According to one version of the Lebor Gabála, the Ulaid united with the Fomorians and gave him battle at Móin Trógaide in County Meath, but a plague fell on them and the leaders of both sides died.
According to another version, agreed by Keating and the Four Masters, Sírna was killed by Rothechtaid Rotha at Alind.
This biography of a member of an Irish royal house is a stub.