O'Neill, Shane, 1530?-1567, Irish chieftain. The eldest son of Con O'Neill, 1st earl of Tyrone, he carried on a bitter feud with his father after Con accepted Henry VIII's nomination of Con's illegitimate son, Matthew, as baron of Dungannon and heir to the O'Neill title. Shane's agents murdered Matthew in 1558, but when Con died in 1559, the English recognized Matthew's eldest son, Brian, as his successor. In 1562, after the murder of Brian, Shane reached a compromise with Queen Elizabeth I in London and was acknowledged as chieftain of Tyrone. Upon his return to Ireland, however, he plunged anew into tribal warfare against his rivals in Ulster. He claimed to be serving Elizabeth in his successful campaign (1564-65) against the MacDonnells, Scottish immigrants on the coast of Antrim. Later, however, he directed his raids and depredations against the English. Defeated by the O'Donnells at Letterkenny, he fled and sought refuge with his former enemies, the MacDonnells, who murdered him.