[2] Making professions of loyalty to the Queen of England in the year following Shane's assassination, Turlough sought to strengthen his position by alliance with the O’Donnells, MacDonnells and MacQuillans.

His conduct giving rise to suspicions, an expedition under The 1st Earl of Essex was sent against him, which met with such doubtful success that in 1575 a treaty was arranged by which O’Neill received extensive grants of lands and permission to employ three hundred Scottish mercenaries.

Still, at the outbreak of rebellion in Munster his attitude again became menacing, and for the next few years he continued to intrigue against the English authorities[3] through clandestine alliances with Spain and Scotland, yet he maintained virtual control of Ulster until 1593, when he was forced by poor health and military setbacks to concede power to his principal rival, Hugh, brother of Brian, whom Turlough had assassinated in 1562 during Shane O’Neill's absence at the court of Queen of England.

Turlough Luineach had successfully survived as "The O'Neill" from 1567 until 1595, a turbulent quarter century that saw the most concerted efforts by the English administration to weaken and marginalise his authority in Ulster.

He is frequently depicted by contemporary English historians as a weak, drunken buffoon, but his continued survival as the O'Neill through this period speaks of his considerable skill as a ruler and of a sustained policy of successful compromise.

Another daughter was married to Sir Donnell O'Donnell, a leading figure in Tyrconnell until his death at the Battle of Doire Leathan in 1590.