Died 583. He was sixth in descent from Coelbad, King of Erin. He built a church or monastery called Killmbain, identified by some as Killyban, Conty Down, and afterwards was consecrated bishop and ruled the cathedral church of Druimleithglais (Down). He was probably the first bishop of that see. His feast is kept on the 30th of March.
- Cornelius Mulcahy. “Saint Fergus, bishop of Downpatrick”. . CatholicSaints.Info. 21 February 2013. Web. 5 September 2015. <>