Diarmait mac Énna
King of Leinster and Dublin
DynastyUí Cheinnselaig
FatherÉnna mac Murchada

Diarmait mac Énna meic Murchada (died 1117) was an early twelfth-century ruler of the kingdoms of Leinster and Dublin.


Diarmait was a member of the Uí Chennselaig, and son of Énna mac Murchada.

Kingship and death

In 1115, Donnchad mac Murchada (died 1115) and Conchobar Ua Conchobair Failge (died 1115), co-kings of Leinster,[1] seized upon the faltering power of the Uí Briain controlled Kingdom of Munster, and launched an attack upon the Kingdom of Dublin. The Dubliners, however, led by the Uí Briain dynast Domnall Gerrlámhach (died 1135), repulsed the invasion, and slew both Donnchad and Conchobar.[2]

The kingship of Leinster thereupon fell to Diarmait himself, who soon after seized control of Dublin, before dying there in 1117. After his death, Domnall Gerrlámhach retook the kingship of Dublin;[3] and Énna Mac Murchada, an Uí Chennselaig kinsman of Diarmait, was elected King of Leinster (died 1126).[4]



  • Duffy, S (1992). "Irishmen and Islesmen in the Kingdoms of Dublin and Man, 1052–1171". Ériu. Royal Irish Academy. 43: 93–133. JSTOR 30007421 – via JSTOR. (Subscription required (help)).
  • O'Byrne, E (2005). "MacMurrough". In Duffy, S. Medieval Ireland: An Encyclopedia. New York: Routledge. pp. 302–303. ISBN 0-415-94052-4.