kingdom · British Isles

Ui Chennselaig

450 CE – 1171 CE (approx.) · capital Ferns

Ruling dynasty of south Leinster, based at Ferns, that produced Diarmait Mac Murchada, whose alliance with the Anglo-Normans changed Irish history.

Origins

The Uí Chennselaig, 'descendants of Énna Cennselach', emerged in the 5th and 6th centuries as the leading dynasty of southern Leinster, in modern Wexford and Carlow. Their royal centre and church were at Ferns, founded by St Máedóc. They competed with the Uí Dúnlainge of the north for the kingship of the Kingdom of Leinster.

Rule and society

Brandub mac Echach, who defeated the high king at Dún Bolg in 598, was their most famous early king. After a long period of northern dominance, Diarmait mac Máel na mBó revived their fortunes in the 11th century, taking Dublin and ruling much of southern Ireland. The family of his descendants, the Meic Murchada or MacMurroughs, became the kings of Leinster.

Decline and legacy

Diarmait Mac Murchada, driven out in 1166, brought Anglo-Norman knights to Ireland. On his death in 1171 Strongbow took Leinster. The MacMurrough Kavanaghs later revived as independent lords in Wexford and Carlow, resisting English rule until the 16th century.

Connections (1)

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Cite this page
APA
The Epoch Institute. (2026). Ui Chennselaig. In The Epoch Institute States Register. https://the-epoch-institute.org/state/ui-chennselaig
MLA
“Ui Chennselaig.” The Epoch Institute States Register, The Epoch Institute, 2026, https://the-epoch-institute.org/state/ui-chennselaig. Accessed .
Chicago
The Epoch Institute. “Ui Chennselaig.” The Epoch Institute States Register. 2026. https://the-epoch-institute.org/state/ui-chennselaig.
Harvard
The Epoch Institute (2026) ‘Ui Chennselaig’, The Epoch Institute States Register. Available at: https://the-epoch-institute.org/state/ui-chennselaig (Accessed: ).

Last reviewed October 2026Random state ↻