Diarmait mac Cerbaill

Diarmait mac Cerbaill
High King of Ireland
Scene from the east face of the Cross of the Scriptures, Clonmacnoise. The figures probably represent Saint Ciarán and Diarmait mac Cerbaill founding Clonmacnoise: "Then Ciarán planted the first stake, and Diarmait son of Cerball was along with him. Said Ciarán to Diarmait when setting the stake, 'Let, O warrior, thy hand be over my hand, and thou shalt be in sovranty over the men of Ireland.'"
Reign539–558
PredecessorTúathal Máelgarb
SuccessorDomnall Ilchelgach and Fearghus
Died565
HouseUí NéillCenél Conaill

Diarmait mac Cerbaill (died c. 565) was King of Tara or High King of Ireland. According to traditions, he was the last High King to follow the pagan rituals of inauguration, the ban-feis or marriage to goddess of the land. The last High King to observe the ancient pagan Feis Temrach or Assembly of Tara which took place on Samhain every three years to pass or renew laws, approve annals and records.

While many later stories were attached to Diarmait, he was a historical ruler and his descendants were of great significance in Medieval Ireland.