Saint Muiredach mac Echdach, also known as Murtagh, was the founding Bishop of Killala, Ireland in the 6th century.

Muiredach was of the Cenél Lóegairi,[2] and connected to the royal family of King Lóegaire mac Néill.

[3] The connection with Patrick doesn't reconcile with Muiredach's being active in the late 6th century, and probably reflects Armagh's interests in Killala.

[2] He appears active in County Sligo, and allegedly met with St. Columba in the year 575, in a town called Ballysadare.

He may also be a patron of the monastery on that island founded by Laisrén mac Decláin.