Tigernach Ua Braín (d. 1088), abbot of Clonmacnoise and Roscommon, putative author of the Annals of Tigernach
Tigernach later became Bishop of Clogher and removed that see to Clones, where he died of the plague in 550.
Sitric, according to the annalist Tigernach, had gone over the sea in 1035, probably for the sake of religious retirement, leaving his nephew as king of Dublin in his place.