Iago ab Idwal Voel (DNB00)
IAGO ab Idwal Voel (fl. 943–979), king of Gwynedd, probably succeeded to the throne of North Wales immediately on the death of his father, Idwal Voel [q. v.], in 943, as joint ruler with his brother Ieuav. In 950, the year of the death of Howel Dda, [q. v.], a long struggle between the representatives of the royal houses of Gwynedd and Dyved commenced. In that year Iago and Ieuav fought a battle at Carno in Montgomeryshire against the sons of Howel, and two years later they carried the war into the latter's territory by making two raids on Dyved. In 954 Howel's sons marched as far north as Llanrwst, and a battle was there fought on the banks of the Conwy, and soon after the North Welsh made a return raid into Ceredigion (Cardiganshire) and laid the country waste, but, the 'Gwentian Chronicle' adds, they were driven back, with great slaughter, by the sons of Howel. Taking advantage of this domestic strife, the Danes, who were at this time established in Ireland and the Isle of Man, made frequent raids upon the coast. Towyn was laid waste by them in 963, and the sons of Herald, Marc and Gotbric (Gotffrid), harried Anglesea,and in 970 brought the whole of the island into subjection (Brut y Tywysogion, sub 970; William of Malmesbury). About 967 the English laid waste the lands of the sons of Idwal (Annales Cambriæ; Brut y Tywysogion), probably because Iago refused to pay the usual tribute to Edgar. Finally, it is said that the payment was commuted for a tribute of three hundred wolves' heads annually, but that this was paid only for three years, because in the fourth year there were no more wolves to be found (Brut y Saeson, in Rhys and Evan's Bruts, p. 390; William of Malmesbury, lib. ii. c. 8). In 967 Iago seized Ieuav, deprived him of his sight, and (according to Brut y Tywysogion) hanged Him. In 972 Edgar, after being crowned at Bath, proceeded to Chester, where (according to the meagre account of the Anglo-Saxon Chronicle) six underkings swore allegiance to him. Florence of Worcester (sub anno 973) and William of Malmesbury (i. 164) mention eight kings by name, among them Iago or Jacob, and they relate how Edgar was rowed down the Dee by them, while he himself steered (see also Brut y Saeson; Hoveden, s. a.) Iago's name also appears as Jacob, with the names of the other seven kings, as a witness to a very suspicious charter of Canterbury, dated at Bath at Whitsuntide 966 (Kemble, Cod. Dipl. No. 519).
Iago's brother, Ieuav, had left behind him a son, Howel, who watched his opportunity to avenge his father's wrongs. About the time of Edgar's visit to Chester, Howel succeeded, with Edgar's support, it is stated (Brut y Tywysogion, p.262), in seizing Iago's throne. Iago probably fled to Lleyn, where Howel and his English allies made a raid about 979. The following year Iago was captured by the Danes, who sailed in a fleet to Chester, and laid the city waste. Howel ab Ieuav thus acquired the complete sovereignty of Gwynedd, and Iago is not heard of again.[Anglo-Saxon Chron.; Annales Cambriæ (both in Rolls Ser.); Brut y Tywysogion and Brut y Saeson in Rhys and Evans's Bruts; Gwentian Chron., ed by Owen; Florence of Worcester; William of Malmesbury; Gesta Regum.]