Brian Ó Flaithbheartaigh (died 1377) was a possible Taoiseach of Iar Connacht and Chief of the Name.
Reign
Brian may have been Taoiseach, but he is not explicitly named as such in his obituary.
Annalistic reference
1377. Walter, son of Sir David Burke; Donnell, son of Farrell, son of the Manach O'Gallagher; Geoffrey O'Flanagan, Chief of Clann-Chathail; Donough, son of William Alainn; O'Carroll, Lord of Ely; Dermot Bacagh Mac Branan, Chief of Corcachlann; Faghtna, son of David O'More; and Brian O'Flaherty, died.
See also
Ó Flaithbertaigh
References
West or H-Iar Connaught Ruaidhrí Ó Flaithbheartaigh, 1684 (published 1846, ed. James Hardiman). Origin of the Surname O'Flaherty, Anthony Matthews, Dublin, 1968, p. 40. CELT: Corpus of Electronic Texts at University College Cork