The Byrne Family History
In the Irish language, 'Ó Broin' means "descendant of Bran". The name has been traced back to the ancient Celtic chieftain, Bran mac Máelmórda, King of Leinster, deposed in 1018, (d. 1052), who belonged to the Uí Dúnlainge dynasty. He was descended from Cathair Mór, an earlier king of Leinster, who was, according to medieval Irish legend and historical tradition, also monarch of all Ireland around 200 AD. The clan's motto is the Latin phrase Certavi et vici, meaning "I have fought and conquered".
In pre-Norman times the O'Byrnes, then known as the Uí Fáeláin sept, inhabited the rich Kildare plains. With the progress of the Anglo-Norman conquest, they were compelled to migrate to the poorer lands and the mountainous country eastwards, later to be denominated as the county of Wicklow.