Murchad mac Brain Mut (died 727) was a King of Leinster from the Uí Dúnlainge branch of the Laigin.
[4] Murchad aligned himself with the pretensions of Cathal mac Finguine (died 742), the King of Munster and in 721 they harried Brega together.
However in December of 722 Fergal and numerous nobles of the Ui Neill were slain at the Battle of Allen (County Kildare) by the Leinstermen led by Murchad.
[7] The saga Cath Almaine preserves the story of this battle and mentions that Murchad's son Dúnchad mac Murchado (died 728) and Áed mac Colggen (died 738) of the Uí Cheinnselaig fought for Leinster.
Áed mac Cellaig (died 719) was slain at the Battle of Finnabair (Fennor, Co.Kildare) in a fight among the Laigin and Crimthann mac Cellaig (died 726) was slain at the Battle of Belach Lice at an immature age.