Sechnassach mac Blathmaic (m. 671) succeeded his father Blathmac mac Aedo Sláine (m. 665) and his uncle Diarmait mac Aedo Sláine (m. 665) as King of Ireland and King of Brega. It belonged to the disastry of Síl nÁedo Sláine of the Uí Néill, so called by his grandfather Áed Sláine (m 604).
The father and uncle of Sechnassach died during a great plague-the buide Chonaill-which struck Ireland from 664 or 665 onwards. While the Chuinn Cétchathaigh Dance, compiled during the reign of Finsnechta Fledach (m. 695), does not include Sechnassach or his brother Cenn Fáelad (m. 675) as Supreme Kings, the Chronicle of Ireland, from which others drink annals Irish, mentions to him like Supreme King to its death. The omission of Sechnassach and his brother Cenn Fáelad could be deliberate since the list was compiled in the reign of the assassin of Cenn Fáelad, Fínsnechta Fledach.
The marriage alliances of Sechnassach that maintained close relations with the kingdom of Leinster. His only recorded marriage was with Findelb ingen Chellaig, who may have been the daughter of Cellach Cualann (m. 715). His daughter, Bé Fáil (m. 741), married Cellach Cualann. Two other daughters of Sechnassach, Murgal and Mumain are known.
Little is recorded in the annals of the reign of Sechnassach, except his death. He was assassinated in November 671 by Dub Dúin, king of Cenél Coirpri, a minor kingdom of Uí Néill near Clonard. His brother Cenn Fáelad would become king after him, probably in 672.
She has appeared in the series of novels and short stories of Peter Tremayne Sister Fidelma. Notes
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