https://en.wikipedia.org/wiki/Bran_Ardchenn

Bran Ardchenn mac Muiredaig was a King of Leinster of the Uí Muiredaig sept of the Uí Dúnlainge branch of the Laigin. He was the son of Muiredach mac Murchado , a previous king.[1] This sept had their royal seat at Maistiu in South Kildare. He ruled from 785-795.

Bran was a rival of Ruaidrí mac Fáeláin of the Uí Fáeláin sept for the throne. In 780 the high king Donnchad Midi campaigned against Leinster and defeated Ruaidrí mac Fáeláin, devastating the territory of his adherents.[2] That same year a congress of the synods of Uí Néill and Laigin was held at Tara and peace was restored.[3] Donnchad may have been campaigning in the interests of Bran and he may have been installed as king at this congress.[4]

In 782 Bran was defeated and captured at the battle of Curragh by Ruaidrí. Brans's allies Mugrón mac Flainn, king of Uí Failgi, and Dub dá Crích son of Laidcnén of the Uí Cheinnselaig were slain.[5] Bran succeeded to the throne in 785.

Bran had married Eithne ingen Domnaill , the sister of Donnchad Midi, the high king of the Clann Cholmáin. This relationship ensured good relations with the high king during his reign.[6] In 794 Donnchad led a hosting into Munster to protect the Laigin.[7]

On May 6, 795 Bran and his wife Eithne , daughter of Domnall Midi were assassinated in a church at Cell Cúile Duma by his successor Fínsnechta Cethardec mac Cellaig of the Uí Dúnchada sept. This was a ruthless political gesture directed at the high king Donnchad.[8]

His sons included Muiredach mac Brain and Cellach mac Brain , both kings of Leinster.