Fogartach (d. 724), son of Niall and king of Tara, belonged to Clann Chernaig Shotail, a lineage of Síl nÁedo Sláine, a constituent dynasty of Uí Néill. His father was a son of the eponymous Cernach Sotal (d. 668); his mother is not named, but four of his brothers or half-brothers feature prominently in the record: Cummascach, Maine (slain 712), Conall Grant (slain 718), and Áed Laigen (slain 722). Although his wife is not recorded, Fogartach had at least five sons: Cernach (slain 738), Flann Foirbthe (d. 748), Fergal (d. 751), Cairpre (exiled 769), and Cummascach (d. 797). He also had a daughter, Dúnfhlaith (d. 774). In 688 his father Niall led a faction of the dynasty in a revolt against the king of Tara, Fínshnechtae Fledach (qv), who had temporarily entered religious retirement; it seems that his bid for power made a sufficient impression to warrant his inclusion in the Old Irish regnal poem of Tara, ‘Baile Chuinn’.
It is likely that Fogartach was a very young man in 697 when, along with his father, he was a signatory to the Law of Adomnán (qv). After his father was killed in 701 by his second-cousin Írgalach (qv), a son or grandson of Conaing (ancestor of Uí Chonaing), pre-eminence within the dynasty passed firstly to this Írgalach and then to Amalgaid (slain 718), grandson of Conaing. Fogartach came to prominence in 704, when he joined forces with Bodbchad, a brother of Murchad Midi (qv) of Clann Cholmáin with the objective of invading Leinster, but they were defeated at Clane. It seems that he spent the following six years consolidating his position in the midlands. The death of Congal Cennmagair (qv) of Cenél Conaill, nominal king of Tara, in 710 was a cue for Fogartach to claim an Uí Néill kingship – although the prestigious kingship of Tara, the focus of much contention since the late 690s, still eluded him. Nonetheless, his political advancement gained him the enmity of Clann Cholmáin, his expulsion from kingship four years later being effected apparently by Murchad Midi. Despite suggestions that his brother Conall Grant planned his expulsion, the balance of the evidence suggests that the latter supported him. In any case, he retired from the scene and went into exile in Britain.
Following the death of Murchad in battle in 716, Fogartach returned to Ireland, and resumed his campaign to secure the elusive kingship of Tara. By this time, his leading opponent was the Cenél nÉogain dynast, Fergal (qv) son of Máel-dúin. In 717 Fogartach and Fergal contested the right to preside at the Óenach Tailten (fair of Tailtiu; Teltown, Co. Meath), a prerogative of the overking of Uí Néill. In the years that followed, the tide turned against Fogartach; it appears that his rivals, Uí Chonaing, collaborated with Fergal. Having defeated and slain Amalgaid at the battle of Kells (718), Fogartach's brother Conall Grant was assassinated on Fergal's orders. Perhaps Fogartach yielded to his rivals at this stage; the sources agree that Fergal was king of Tara (even if the length of his reign is disputed) and that he led the army of Leth Cuinn (the northern half of Ireland) during his fateful invasion of Leinster in 722. More to the point, two of Fogartach's kinsmen, his brother Áed Laigen and his nephew Ailill son of Conall Grant, were killed in Fergal's service.
His rival's death at the battle of Almu (the Hill of Allen) in December 722, however, gave Fogartach his long-awaited opportunity to seize the kingship of Tara. He is perhaps to be identified with the kenning ‘Glúnshalach’ in ‘Baile Chuinn’; he is also admitted by ‘Baile in Scáil’ and by the Middle Irish regnal lists – where he is accorded a reign of one year, although the Fragmentary Annals (§180) acknowledge that he may have reigned for two years. Shortly after his accession, he was defeated by the Leinstermen at Tailtiu – which may point to a northward thrust by Leinster forces in the wake of their victory at Almu. In the event, there is no notice of further conflict from this direction.
Fogartach was killed in 724 by the leading dynast of Uí Chonaing, Cináed Cáech (qv) son of Írgalach, at the battle of Cenn Deilgthen (possibly Kildalkey, Co. Meath). According to tradition, he was buried at Clonard. A poem preserved in the Fragmentary Annals implies that his enemies were supported by Domnall Drech-derg (red-countenance), probably to be identified with Domnall Midi (qv) of Clann Cholmáin. Friction between that dynasty and Fogartach's family seems to have persisted, Fogartach's son Cairpre being driven into exile in 769 by Donnchad Midi (qv). Two of Fogartach's sons reigned as kings of Deiscert Breg (southern Brega; north Co. Dublin extending into east Meath), namely Fergal (d. 751) and Cummascach, who died in religious retirement in 797 – presumably at a rather advanced age. Fogartach's descendants, based at Loch Gabor (Lagore crannóg), ruled southern Brega till the eleventh century.