The Leinster king Bran Mut mac Conaill (died 693) assembled the Leinster forces and sent Saint Moling (d. 697), the abbot of Ferns, to negotiate with Fínsnechta. Mo-Ling tricked Fínsnechta into remitting the tribute. As a result, Saint Adomnan grew angry with the high king and cursed saying that his descendants would have no fame. Fínsnechta did penance to Adomnan and was forgiven for remitting the Boruma. In 688, Fínsnechta abdicated to become a monk, but he left the clerical life and resumed the kingship in 689. This return to power may have been a result of the break-out of a civil war among the Síl nÁedo Sláine when Niall mac Cernaig Sotal (died 701) of the Uí Chernaig sept of south Brega defeated Congalach mac Conaing Cuirre (died 696) of north Brega at the Battle of Imlech Pich in 688. Also, Áed mac Dlúthaig (died 701) of the Síl nDlúthaig sept killed Diarmait Dian mac Airmetaig Cáech, the King of Uisnech, of the Clann Cholmáin in 689. He was killed, along with his son Bresal, by his kinsmen Áed mac Dlúthaig and Congalach mac Conaing Cuirre at Grellaigh Dollaith. According to the "Annals of Tigernach", this occurred in battle, but the "Fragmentary Annals of Ireland" state that Finsnechta was murdered in a tent by Congalach. Congalach succeeded Fínsnechta as King of Brega, and Loingsech mac Óengusso, of the northern Cenél Conaill branch of the Uí Néill, was the next High King. Fínsnechta's descendants the Clan Fínsnechtai played no important role after him. Fínsnechta was survived by a son named Ailill who was killed in 718. The earliest surviving list of High Kings of Ireland, that in the "Baile Chuind Chétchathaig" was apparently compiled in Fínsnechta's reign.