B. 949, s. of Domnaill of Mide and Donnflaith; high-king of Ireland 980–1002, 1014–22; d. Cro-inis, 2 Sept. 1022.
Leader of the Clann Cholmáin branch of the southern Uí Néill by 975/6, Máel Sechnaill succeeded Domnall (of the northern Uí Néill) as high-king in 980, under the alternating system of succession. In a reign dominated by battles against the Danes, and attempts to crush rivals, his struggles against the Munster king Brian Bóruma (Boru) were briefly halted at Clonfert (997), where each recognized the other's supremacy in their respective halves of the country. Although jointly defeating the Danes at Glenn Máma (999), conflict resumed and Máel Sechnaill was forced to submit to Brian in 1002. After Brian's death at the battle of Clontarf (1014), Máel Sechnaill resumed the high-kingship until his own death, when the alternating system of succession ended and a long interregnum followed.
Subjects: British History — European History.