Nuala O'Donnell was a member of the O'Donnell dynasty in sixteenth century Ireland who took part in the 1607 Flight of the Earls. She was the daughter of Sir Hugh O'Donnell, the Gaelic lord of Tyrconnell and head of the O'Donnells. Her siblings include her full brother Sir Donnell O'Donnell and her half-brothers Hugh Roe O'Donnell, Rory O'Donnell and Cathbarr O'Donnell. She was also a sister-in-law of Hugh O'Neill, Earl of Tyrone due to his marriage with her sister Siobhán. Much of her family became engulfed in the violent O'Donnell succession dispute of the 1580s and 1590s, as various claimants attempted to secure the right to succeed her father even while Sir Hugh was still alive. Her elder brother Donnell was killed in battle in 1590 by Scottish redshank mercenaries hired by her stepmot