O'Byrne family

According to historian C. Thomas Cairney, the O'Byrnes were one of the chiefly families of the Uí Dúnlainge who in turn were a tribe from the Dumnonii or Laigin who were the third wave of Celts to settle in Ireland during the first century BC.

[2] His son Fiach McHugh O'Byrne took over the chieftainship and together with the Pale lord James Eustace, 3rd Viscount Baltinglass, continued hostilities to the English administration.

A large English force under the Lord Deputy of Ireland Earl Grey de Wilton was sent to subdue them, only to be ambushed and defeated at the battle of Glenmalure on 25 August 1580, losing over 800 dead.

[2] Fiach was betrayed and killed by the forces of the Lord Deputy of Ireland at Fananerin on 8 May 1597.

The Leabhar Branach, a book of Irish-language poetry in praise of the clan, was compiled in the early 17th century.