Uí Briúin

The Uí Briúin were an kin-group. Their ous was, son of , an elder brother of. They formed part of the, along with the and , putative descendants of Eochaid Mugmedon's sons Fiachra and Ailill. The Uí Ailello were later replaced as the third of the Three Connachtas, by genealogical sleight of hand, by the.

Connacht was ruled in early times by the Uí Fiachrach, the Uí Briúin only becoming the dominant force in Connacht in 7th and 8th centuries.

The Uí Briúin divided into multiple septs, the major ones being:


 * The Uí Briúin Ai, named for the region they controlled&mdash;Mag Ai, the lands around the presumed ancient centre of Connacht, in modern . Major divisions of the Uí Briúin Ai were the Síl Muiredaig, from whom the many high medieval dynasties of  (O'Connors) were descended, and the Síl Cathail.


 * The Uí Briúin Bréifne, whose high medieval kingdom of lay in modern  and . The  and Ó Ruairc dynasties were among the septs of the Uí Briúin Bréifne.


 * The Uí Briúin Seóla, who were centred around in modern.


 * The Uí Briúin Umaill, in far west Connacht, on the shores of, modern.

Reference

 * , Irish Kings and High-Kings. Batsford, London, 1973. ISBN 0-7134-5882-8