In his time there was a rivalry between the northern septs of the Síl nÁedo Sláine, including the Uí Chonaing sept of Cnogba (Knowth) and the Síl nDlúthaig of Fir Cúl, with the southern sept of the Uí Chernaig. Conall's brother
Niall mac Cernaig Sotal had been killed by the Uí Chonaing king of Brega,
Írgalach mac Conaing Cuirre (died
702) The kingship of Brega at this time was in rivalry between the septs. Two contemporaries were also considered kings of Brega around this time,
Amalgaid mac Congalaig (died
718) of the Uí Chonaing, and Conall Grant's nephew,
Fogartach mac Néill (died
724). Conall is among the guarantors of the
Cáin Adomnáin (Law of Innocents) proclaimed at the
Synod of Birr in
697 where he is given the title King of Deiscirt Breg or southern Brega. These titles were added to the list of guarantors in
727 and the first use of the title King of South Brega in the
Annals of Ulster is not until 751 In 712, his nephew
Maine mac Néill was slain in battle versus
Flann mac Áedo (died
714) of the Síl nDlúthaig. In 714, his nephew Fogartach was deposed from the kingship and went to Britain possibly by the high king Fergal mac Máele Dúin (died
722) of the Cenél nEógain. Conall may have acquired the rule of Brega and in
715 he was responsible for the assassination of
Murchad Midi, the King of
Uisnech from the
Clann Cholmáin, possibly the deputy of Fergal. His nephew Fogartach returned to the rule of Brega in 716. Then, in 718 Conall fought the Battle of Cenannas (near Kells) and defeated and slew Amalgaid of Cnogba and his brother Fergal, along with their allies, Gormgal mac Áedo of Síl nDlúthaig and Tuathal Ua Fáelchon of Clann Cholmáin Bicc. The high king Fergal intervened and had Conall killed two months later. The descendants of Conall known as the Síl Conaill Graint based at Calatruim developed a rivalry with the descendants of his brother Niall, the main Uí Chernaig line at Lagore, within the southern Brega septs of Síl nÁedo Sláine. Conall's son
Niall mac Conaill Graint (died
778) was a King of Southern Brega. Another son, Ailill mac Conaill Graint (died 722) was slain at the Battle of Allen where the men of Leinster defeated the Ui Neill. ==Notes==