Cormac mac Cuilennáin, king of Munster (Ireland)
Cormac mac Cuilennáin (died 13 September 908) was an Irish bishop and the king of Munster from 902 until his death at the Battle of Bellaghmoon. He was killed in Leinster.

Cormac was regarded as a saintly figure after his death, and his shrine at Castledermot, County Kildare, was said to be the site of miracles. He was reputed to be a great scholar and is credited with the authorship of the Sanas Cormaic (Cormac's Glossary) and the now-lost Psalter of Cashel, among other works. The reliability of some of the traditions concerning Cormac is doubtful. His feast day is September 14.