O'Neill (Ó Néill), Conn ‘Bacach’ (c.1484–1559), 1st earl of Tyrone , was son of Conn O'Neill (qv) (d. 1493), king of Tír Eóghain, and his wife Lady Eleanor (d. 1497), daughter of Thomas FitzGerald (qv), 7th earl of Kildare. In 1498 Conn Bacach (‘the lame’) first surfaces in the written record as assassin of his father's murderer, Enrí Óg O'Neill (qv), king of Tír Eóghain, on 21 July. In 1519 he succeeded his half-brother Art as lord of Tír Eóghain, and remained allied to the house of Kildare. When Gerald FitzGerald (qv), 9th earl of Kildare, was called to account for his lord deputyship in 1520, O'Neill responded to the earl's overtures by raiding the Pale. In July 1520 Thomas Howard (qv), lord lieutenant of Ireland, met with O'Neill, who promised to be loyal. Henry VIII, encouraged by this declaration, sent O'Neill a collar of gold, and the archbishop of Armagh urged him to remain true to his pledge. On Kildare's return to Ireland (January 1523), O'Neill proved himself a true Geraldine, as shown by his presence on Kildare's campaign (1523) against the O'Connor Falys and the O'Mores, and his symbolic carrying of the sword of state at Kildare's assumption of the office of lord deputy (4 August 1524).
It was probably during the mid 1520s that Alison Kelly presented her son Matthew, then aged about 16, to O'Neill, claiming that the boy was his natural son. O'Neill recognised him as Matthew (Feardorcha) O'Neill (qv), and declared him his son and heir. This action precluded his legitimate sons from succeeding him. Possibly O'Neill feared the ambitions of his legitimate son Shane O'Neill (qv) who was then still under the fosterage of Ó Donnghaile.
Throughout the 1520s O'Neill, through talented diplomacy and some military skill, battled his great rival Aodh Dubh O'Donnell (qv), lord of Tír Conaill, for regional supremacy and tenure of the disputed Inishowen peninsula. On the whole, the O'Donnells proved too strong for him, as was shown when Manus O'Donnell (qv) successfully built a castle at Lifford in the middle of a disputed region. O'Neill's intrigues continued, but the O'Donnells were generally militarily dominant. In 1532, however, O'Neill exploited the chaos within the O'Donnell lordship by aiding Manus O'Donnell against his father, Aodh Dubh. During the 1534 rebellion of Thomas FitzGerald (qv), Lord Offaly, O'Neill joined him and sent troops to aid the FitzGerald cause. He, however, was astute enough to realise that Henry VIII was going to crush the Kildares. Even before Thomas's surrender (August 1535), O'Neill had concluded a peace with Sir William Skeffington (qv), lord lieutenant of Ireland, at Drogheda (26 July). In 1536 he renewed his submission to Lord Leonard Grey (qv), but continued his interference in Gaelic lordships around Tír Eóghain. Early in 1539 he formed an alliance with Manus O'Donnell to protect the young Kildare heir Gerald Fitzgerald (qv), 11th earl of Kildare. Their expedition into the Pale met with initial success, but was routed by Grey at Bellahoe that year. O'Neill remained recalcitrant, and expeditions were regularly launched into Tír Eóghain throughout 1540–41.
By early 1542 O'Neill was ready to listen to the overtures of Sir Anthony St Leger (qv), lord deputy of Ireland. In May 1542 O'Neill renounced the pope as head of the church in favour of Henry VIII, and promised to be an obedient subject. The following month, he (with the encouragement of the government) concluded a peace with Feidhlimidh Ruadh O'Neill of the Fews. The further change in O'Neill's status was evident, when he was created earl of Tyrone by Henry VIII (October 1542). His heir Matthew was recognised by his new style of baron of Dungannon. Tyrone's changed fortunes continued. He became a privy councillor in 1543, and was granted the lands of Ballygriffen, Co. Dublin, in the following year. During 1544–9 the new peer of the realm relentlessly pursued private wars against his O'Neill rivals, the O'Donnells, and Maguire. The rising strength of the Scots in the Antrim Glens, due to the growing weakness of the O'Neills of Clann Aodha Buidhe, caused huge problems for Tyrone on his eastern borders. This perilous situation was further complicated by the aggressions of army commanders such as Sir Nicholas Bagenal (qv). In response Tyrone brought his complaints to the council, where he was called a traitor. A greatly aggrieved Tyrone returned to Tír Eóghain and became more apprehensive of the power of Dungannon. In alliance with Shane, he attacked Dungannon and Turlough Luineach O'Neill (qv). At the prompting of Dungannon, who declared himself the ‘king's man’, Lord Deputy James Croft (qv), arrested Tyrone. The advantage accrued by Dungannon was brief, and by the close of the year Shane was in the ascendant.
In summer 1552 Dungannon's forces were destroyed by Shane, who called for the release of Tyrone as part of the price of peace. Edward VI wrote reassuringly to Tyrone, and sanctioned the old man's release. Tyrone, once free, turned to Dungannon, and they set about reconstructing their lordship by attacking Shane's allies. Their efforts met with defeat (1554); Shane was able to contain their threat, and forced them to flee to the Pale during 1557. They were, however, restored after Shane's defeat at the hands of An Calbhach O'Donnell (qv), lord of Tír Conaill, that year. When Shane's assassins killed Dungannon, Tyrone fled for his life to the Pale. There he died in the bishop of Meath's house in July 1559.
Tyrone's talent as a diplomat and a soldier served him well in the dynastic intrigues of Tudor Ireland. But the O'Neill dynasty, bitterly divided, could not use its full military potential to support his diplomatic skills. This dynastic weakness forced O'Neill to continually temporise and intrigue. Naturally, he always gravitated to the dominant power within the land whether it was the Kildares, the Tudors, Dungannon, or Shane. This was often a successful ploy on his part to get what he wanted. By the 1550s, however, he was a spent force.