His death date is given in the Annals of Tigernach in 489. The Book of Leinster gives him a reign of 24 years giving a possible reign of 465–489. Nothing is recorded of him in the annals other than his death date.
In the period following the destruction of Emain Macha after 450, Ulidia underwent a recuperation in which the Dal Fiatach emerge as the overlords and Muiredach as the first historical king. According to the Dal Fiatach genealogies, he received the blessing of Saint Patrick. The early seat of power of this dynasty appears to have been in County Louth at Óchtar Cuillche (Colland) at Collon, south of Ardee, County Louth and his descendants are said to have split up their inheritance here in the early 6th century.
- Byrne, Table 6; Charles-Edwards, Appendix XXI; Mac Niocaill, pg.74
- Annals of Tigernach, AT 489.3
- Mac Niocaill, pg.73
- Ó Cróinín, pg.219
- Annals of Tigernach at  at University College Cork
- Byrne, Francis John (2001), Irish Kings and High-Kings, Dublin: Four Courts Press, ISBN 978-1-85182-196-9
- Charles-Edwards, T. M. (2000), Early Christian Ireland, Cambridge: Cambridge University Press, ISBN 0-521-36395-0
- Dáibhí Ó Cróinín (2005), A New History of Ireland, Volume One, Oxford: Oxford University Press
- Gearoid Mac Niocaill (1972), Ireland before the Vikings, Dublin: Gill and Macmillan
- Book of Leinster,Rig Ulad at CELT: Corpus of Electronic Texts at University College Cork