[1] This sept had their royal seat at Naas in the eastern part of the Liffey plain, Airthir Liphi.
The men of Leinster had submitted to the authority of the high king Donnchad Midi (died 797) of the Clann Cholmáin in 770.
Ruaidrí and the king of the southern Uí Cheinnselaig, Cairpre mac Laidcnén, were defeated at the Battle of Óchtar Ocha (at Kilcock, near Kildare).
[3] the Annals of Ulster state of this event:"Great hosts ... pour forth for themselves streams of gore; a company parts with Life in the overthrow of Óchtar Ocha."
[4] This campaign by Donnchad may have been in support of his son-in-law Bran Ardchenn mac Muiredaig (died 795), a rival of Ruaidrí.