Dictionary of National Biography, 1885-1900/O'Brien, Conor (d.1539)
O'BRIEN, CONOR (d. 1539), prince of Thomond, was eldest son of Turlough O'Brien (d. 1528) by his wife Raghnailt, daughter of John Macnamara, chief of Clancullen. The ‘Four Masters’ say of Turlough that ‘he, of all the Irish in Leath Mogha, had spent the longest time in [acts of] nobility and hospitality, the worthy heir of Brian Boroimhe in maintaining war against the English’ (Annals, v. 1393). Conor succeeded to the throne in 1528, when his brother Donogh was nominated tanist. Donogh, ‘a man of hospitality and nobleness,’ died, however, in 1531, and gave place to a third brother, Murrough O'Brien, first earl of Thomond [q. v.] A fourth brother, Teige, was killed in 1523, when fighting against the Earl of Ormonde at the ford of Camus on the river Suir.
Conor O'Brien became prince of Thomond at a very critical period. To check the preponderance of the Earl of Kildare, the Butlers had been supported by the English court. In the intrigues which ensued Kildare got the better of his enemies, and became deputy instead of Butler in 1524. O'Brien's family was divided within itself in the long-continued struggles between the two great rival houses. Conor had married, for his first wife, Anabella de Burgh, daughter of the MacWilliam, and by her had a son Donogh. On the death of his first wife he married Ellen, daughter of James FitzJohn Fitzgerald [q. v.], fourteenth earl of Desmond, by whom he had five sons. The Geraldines, who were akin to O'Brien's second wife, formed an alliance with Conor O'Brien and the sons of his second marriage. The Butlers, on the other hand, gained the adherence of Donogh, O'Brien's eldest son by his first wife, and this connection was strengthened by a marriage between Donogh and Helen Butler, daughter of the Earl of Ossory. When the Geraldines were ravaging the lands of the Butlers in 1534, Conor, who was allied with the attacking party, wrote a letter to the Emperor Charles V, dated 21 July 1534, in which he asked help, and offered to submit to his authority (Letters and Papers of Henry VIII, vii. 999). A battle took place at Jerpoint, in which Donogh O'Brien, on the side of the Butlers, was wounded; but the arrival of Skeffington with reinforcements, and the capture of Maynooth in 1535, caused the Geraldines to lose ground. Thomas Fitzgerald, tenth earl of Kildare [q. v.], surrendered the same year. But the O'Briens, with the exception of Donogh, still continued rebellious, though Conor made promises of good behaviour (cf. State Papers, ii. 287). In 1536 Lord Leonard Grey, the new lord-deputy, advanced, under Donogh's guidance, against Conor, and captured O'Brien's Bridge over the Shannon. For six months early in 1537 Conor kept safely in Thomond Gerald FitzGerald, eleventh earl of Kildare [q. v.], whom the English government were anxious to capture. The earl afterwards escaped, by aid of the O'Donnells, into France. An expedition of 1537 resulted in O'Brien's making peace for a year, by a solemn agreement entered into at Limerick. He died in 1539, and was succeeded by his brother Murrough (d. 1551) [q. v.]
Conor O'Brien was the last independent prince in Thomond. His son Donogh by his first wife, by virtue of the limitation of the peerage granted to his uncle Murrough, became in 1551 second Earl of Thomond. From 1543 to 1551 he was Baron Ibrickan, this title having been given him at the pacification of 1543. He was father of Conor O'Brien, third earl of Thomond [q. v.]
By his second wife Conor had Donald, Torlogh, Teige, Murrough [q. v.], and Mortogh.
[O'Donoghue's Hist. Mem. of the O'Briens, chaps. xi. xii.; The Four Masters, ed. O'Donovan, vol. ii.; Bagwell's Ireland under the Tudors, vol. i.; State Papers, i. 601, ii. and iii. passim; Cal. State Papers, Irish Ser. 1507–73; Carew MSS. 1509–74.]