Fiach MacHugh O' Byrne


Fiach MacHugh O’Byrne, also known as Feagh or Fiach mac Aodha Ó Broin(1534-1597), was a prominent Irish leader during the Elizabethan wars against the Irish clans. As the Chief of the Name of Clann Uí Bhroin (Clan O’Byrne) and Lord of Ranelagh, he played a significant role in the conflicts between the Irish clans and the English Crown, one such raid which resulted in the burning of Crumlin.
O’Byrne controlled a vast territory in the Wicklow mountains, south of Dublin, during Queen Elizabeth I’s reign. His stronghold was located at Ballinacor in Glenmalure, a strategic position where they maintained a fort, bridge, and castle. The O’Byrnes’ loyalty varied among different branches, with the Ranelagh O’Byrnes posing a constant threat to Tudor authority through raids on the lowlands.
Despite some early loyalty, O’Byrne’s father and the Ranelagh O’Byrnes had supported rebels during the Desmond Rebellions in 1569. Fiach himself became a notable figure known for his wily and skillful tactics, betraying ambitions to undermine Tudor authority in Ireland.
His involvement in various conflicts, such as the murder of Robert Browne in 1572 and support for the pretender to the lordship of Leix in 1577, led to clashes with English forces. The most notable engagement was the Battle of Glenmalure in 1580, where O’Byrne’s forces decisively defeated the English army led by Lord Deputy Arthur Grey.
Despite occasional setbacks, O’Byrne remained a thorn in the side of English authorities. His alliances with other Irish clans and involvement in rebellions persisted. In 1595, Crumlin was attacked and burned to the ground by Walter Reagh FitzGerald and some of the Fiach’s sons. During the raid, the assailants stripped the lead roof off the local church to be used for the manufacture of bullets. In 1597, after relentless pursuits by the English, O’Byrne was captured and executed by Captain Thomas Lee.
O’Byrne’s legacy is overshadowed by accounts of other Irish leaders like Hugh O’Neill, but he played a crucial role in resisting English authority. His descendants faced challenges and continued to participate in subsequent conflicts, surviving the Nine Years War and receiving land grants in 1606.
In popular culture, O’Byrne is celebrated in the song “Follow me up to Carlow” by P.J. McCall and is the subject of “The Marching Song of Fiach Mac Hugh” by the Irish Folk metal band Cruachan. The Book of O’Byrne, a collection of Irish bardic poetry, was compiled under his patronage.
Efforts to trace modern descendants of Fiach mac Aodha Ó Broin have not met notable success, leaving his historical impact enduring but his direct lineage elusive.

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Connection with area: Leader of Gaelic Leinster who clan attacked and burned the suburb of Crumlin