Áed (d. 700), bishop of Sléibte (Sletty, on the border of Co. Carlow and Co. Laois), which belonged to the Uí Bairrche sept of Laois, was son of Broccán according to the genealogies. Because of the growth in Armagh's influence and claims to metropolitan status in the latter half of the seventh century, following on her acceptance of the Roman method of computing the date of Easter, he gave his church at Sletty over to the protection of Armagh during the abbacy of Ségéne (661–88), offering ‘his kin and his church to Patrick forever’. The ‘Additamenta’ in the Book of Armagh describe it cryptically thus (16, 1–2, p. 178): ‘Bishop Áed was in Sletty. He went to Armagh. He brought a testament to Ségéne, to Armagh. Ségéne gave his testament back to Áed and Áed granted his testament and his kindred and his church to Patrick forever. Áed left his testament with Conchad. Conchad went to Armagh. Fland Feblae [successor to Ségéne] confirmed its meaning [i.e. its terms] to him and moreover accepted him as abbot.’
Áed is probably the author of the versified Life of St Patrick (qv) known as ‘Fiacc's hymn’ (erroneously credited to Fiacc (qv) (late 5th cent.), bishop of Sletty). His name appears, with that of his spiritual disciple Muirchú (qv), in the guarantor list of the Law of Adomnán (qv), which was promulgated at a synod in Birr in 697. Muirchú dedicated his ‘Vita S. Patricii’ to him as his spiritual mentor and director of the project, designating him ‘my lord Áed’ in the prologue. It is probable that the church at Sletty had preserved some written material on Patrick, which served as one of Muirchú's sources. Áed died in 700 as an anchorite in Armagh.