O'Byrne, Fiach MacHugh (c.1544–1597), lord of Crioch Raghnuill and leader of Gaelic Leinster, was eldest son of Aodh O'Byrne (qv) (d. 1579), lord of Crioch Raghnuill, and his first wife Sadhbh, daughter of Feilim O'Byrne of Clonmore. Fiach and his only full sibling (and perhaps twin), Elizabeth, were probably born in 1544 at their grandfather Seaán's residence at Ballinacor, Glenmalure. About 1549 Fiach's parents divorced; his father had taken as his wife Sadhbh, daughter of Art Óg O'Toole (qv) of Castlekevin, before August 1550. The boy's mother later married Diarmait Dubh Kinsella, lord of Uí Cheinnsealaigh in north Wexford.
Early campaigns, 1560–70 Fiach's father Aodh was determined to become the leader of Gaelic Leinster and advanced his family's status through his patronage of poets and military support of the O'Connor Falys and O'Mores in Laois and Offaly during the 1550s and 1560s. Under the tutelage of his father, Fiach emerged as a pragmatic but hard-line warlord in the 1560s. In the early 1560s he married his cousin Sadhbh, daughter of Domnall mac Cathaoir Kavanagh (qv) (MacMurrough Kavanagh), and had four sons and two daughters by 1569. As the 1560s wore on, Aodh's attacks became more ambitious and predatory, which may indicate Fiach's influence. The young warlord first attracted the government's attention in January 1563, when he and Aodh received pardons for their probable involvement in Richard Keating's disturbances in Wexford (summer 1562). They were pardoned again (December 1563) after their kidnaps of George Harvey and Henry Davells, and their attack with the O'Tooles on the Talbot family. In August 1564 they and some Kavanaghs attacked Tibbot Walsh, and the frequency of their raids and their extortion began to concern the government in December 1564. In late 1565 Aodh's followers killed some men of Sir Francis Herbert. When called to account in February 1566, Aodh promised to surrender Fiach but defaulted on his pledge. Their steady rise did not go unnoticed and earned them fresh pardons (May 1567, April 1569). Sir Francis Agard, seneschal of Crioch Branach and Crioch Raghnuill since 1566, realised the danger that Fiach posed. However, his friendship with Aodh prevented him from taking any punitive action.
In 1569 the revolt of the Kavanaghs of Idrone, Co. Carlow, and Sir Edmund Butler (qv), brother of Thomas Butler (qv), 10th earl of Ormond, gave Fiach his chance to cause havoc. It was the award of Idrone by the lord deputy, Henry Sidney (qv), to Sir Peter Carew (qv) the elder that caused the Butlers and Kavanaghs to revolt. Sir Edmund submitted to Ormond (September 1569) and was imprisoned in Dublin castle, but in November 1569 he escaped with the help of Aodh's sons to Glenmalure. While there, Sir Edmund had an affair with Fiach's wife, resulting in Sadhbh's divorce from Fiach, her later marriage to Butler, and considerable enmity between the two men.
Leader of Gaelic Leinster, 1571–8 In the 1570s Fiach established himself as the leader of the Leinster Irish. In 1571 Ruaidhrí (Rory) Óg O'More (qv) (d. 1578) of Laois joined him and attacked the Pale. Later Fiach and his brother-in-law Brian MacMurrough Kavanagh (qv) were implicated in the murder of Robert Browne of Mulcranan, an influential south Co. Wexford landowner (21 April 1572). In July 1572 Agard killed Fiach's brother for his alleged part in the murder of Browne. In August 1572 the seneschal of Wexford, Sir Nicholas White (qv), returned from England. White, Browne's father-in-law, obtained the support of Elizabeth to take action against Fiach. Within days of his return, White attacked Crioch Raghnuill, but his assault failed to subdue Fiach. In response Fiach and Brian Kavanagh ravaged Wexford, and with Ruaidhrí wreaked mayhem throughout Leinster. In February 1573 Aodh, Brian Kavanagh, and Fiach were pardoned after withdrawing their support from the actual murderers, Matthew and Robert Furlong.
Throughout 1573 Aodh and Fiach renewed contact with Gerald Fitzgerald (qv), 15th earl of Desmond. Desmond hoped that Ruaidhrí (who helped him to escape from Dublin in 1573) and the O'Byrnes would rise up in Leinster during 1574. In preparation for war, Aodh recruited mercenaries and made two marriage alliances to strengthen his regional position. One of these alliances was Fiach's marriage in 1573 to Rose O'Toole (qv), daughter of Fiach O'Toole (qv) (d. 1578) of Castlekevin and Rose Basnett (fl 1600). The other was Ruaidhrí's union in November 1573 with Mairghréag, Fiach's favourite sister. On his return from their wedding, Fiach was ambushed by the sheriff of Kildare, Sir Piers FitzGerald (sl. 1594). However, Fiach turned the tables on the sheriff, capturing him and carrying him off as a hostage to Glenmalure. Once in the safety of the mountains, Fiach demanded a ransom of £800 before he would consent to free FitzGerald. In spite of Agard's negotiations, the O'Byrnes stood firm, defying several attempts to rescue the unfortunate sheriff before finally releasing him, probably in early 1574.
Fiach revolted as planned in March 1574, burning the country to Dublin, while Ruaidhrí raided the southern Pale. In February 1575 Gerald FitzGerald (qv), 11th earl of Kildare and governor of the Pale's south-western border, was arrested on suspicion of conspiring with the O'Byrnes and Ruaidhrí to force Elizabeth to make him lord deputy. Kildare was imprisoned in England, but nothing was proved and he returned to Ireland in 1577. During the earl's absence, Ruaidhrí and Fiach burned throughout Co. Kildare. During Lord Deputy Sidney's circuit through east Leinster (November–December 1575) Aodh met him without protection, but Fiach remained aloof. In June 1576 Ruaidhrí was pardoned by Sidney, who hoped to incorporate him within the Laois plantation. Sidney also hoped to address Fiach's discontent, and Agard was dispatched to bring him to Dublin in July 1576.
The ceaseless intimidation by Sir Francis Cosby (qv), seneschal of Laois, forced Ruaidhrí to revolt in February 1577. Massacres such as that of the defenceless Muircheartach O'More (lord of Slemargy and Ruaidhrí's alleged ally) by Cosby and Robert Harpoole, sheriff of Carlow, profoundly shocked Gaelic Leinster. This act sparked fighting that consumed the midlands and spread into Kildare and Carlow, where Ruaidhrí burned Naas and Leighlinbridge (May 1577). O'More captured Sir Henry Harrington and Alexander Cosby (November 1577). During a rescue attempt by the planters, Ruaidhrí's wife Mairghréag was beheaded and two of his sons slaughtered; although seriously wounded, Ruaidhrí managed to escape. But the killing of Fiach's brother Seaán within days of Mairghréag's death suggests that the O'Byrnes intervened to support the beleaguered Ruaidhrí. After his recovery, he led revenge attacks from Crioch Raghnuill on Carlow and Kildare. On 30 June 1578 Ruaidhrí was killed in a skirmish with Brian MacGillapatrick (qv), baron of Upper Ossory.
The deaths of Ruaidhrí and his wife alienated Fiach from the government. He swore revenge and undertook to bring up both of their children in Glenmalure. Ruaidhrí's demise, combined with the deaths of Brian Kavanagh and Fiach O'Toole of Castlekevin during 1578, left Fiach the only lord powerful enough to lead Gaelic Leinster. To counter the encroachments of the government, he sought to create a unified provincial opposition. Even though he was Gaelic Leinster's most powerful lord, he could not claim its kingship without losing support among the Kavanaghs. Instead, he played kingmaker, advanced his clients in several dynastic struggles, and compelled them to swear fealty to him. In summer 1578 Thomas Masterson, seneschal of Wexford since 1573, with Sir Peter Carew the younger, led raids on Crioch Raghnuill. This struggle spiralled out of control and much of Wexford was destroyed. On 21 September 1578 Fiach submitted in Christ Church cathedral, Dublin, and bitterly complained about Masterson. Consequently, Fiach was committed to the custody of Harrington, Agard's son-in-law and successor as seneschal since 1577. Within days he was released and submitted alongside Aodh at Castledermot, Co. Kildare (30 September 1578). Later Masterson arranged for Fiach to be assassinated at a proposed parley. Fiach, however, struck first and routed Masterson's troops as they waited to ambush him.
The Baltinglass rebellion, 1579–81 Throughout 1579 Fiach and Aodh cooperated with the government. Aodh's death that year freed Fiach from all parental restraint. However, before the close of 1579 the government intercepted a letter from Desmond, urging Fiach and James Eustace (qv), 3rd Viscount Baltinglass, to join him in a war for catholicism. With Baltinglass, Fiach planned a rebellion that would unite the catholics of Ireland. Fiach's religious zeal even impressed the papal legate, Dr Nicholas Sander (qv). The rebellion of the senior O'Byrnes against Harrington (January 1580), Harrington's attempted assassination of Fiach and his hanging without trial of Tibbot O'Toole, and Masterson's massacre of unarmed Kavanaghs (10 April) propelled Fiach into conflict earlier than he planned. In June 1580, with Gerald Odhar O'Byrne, he invaded Wexford, devastated Masterson's lands, and (with Muircheartach Óg Kavanagh) burned the Carew estates in Idrone. Baltinglass joined Fiach in July. After his sack of Newcastle McKynegan in east Wicklow during late July, Fiach unfurled the papal colours; he defeated the new lord deputy, Lord Grey de Wilton (qv), at Glenmalure (25 August). His success was quickly followed by his destruction of several villages and the defeat of Wicklow's garrison (September–October 1580).
In spring 1581 the tide began to turn. Sir William Stanley (qv) burned Fiach's home at Glenmalure, and several reverses were inflicted on his supporters in Wexford. While Fiach and Baltinglass remained elusive and continued to strike at will, they realised that Grey was sapping their strength and agreed a ruse to allow their forces to regroup: Fiach would submit, and Baltinglass would escape to Spain and seek support from Philip II. In his absence, Baltinglass appointed Fiach commander-in-chief of the Leinster army. In July 1581 Fiach's offer to submit was accepted by Grey. During the protracted negotiations for his surrender (August), Fiach mocked Grey and refused to accept his pardon unless Baltinglass was included. On 28 August Fiach finally submitted and Baltinglass made his preparations to flee, which he did with Fiach's help in November 1581. Shortly afterwards (December) Fiach aroused the government's ire by hanging Gerald FitzGerald, who allegedly had evidence of Kildare's covert support of Baltinglass.
Submission and intrigue, 1582–90 Despite his preparations and his sister's marriage to Tadhg O'Connor Faly (qv), Fiach's hopes for a Spanish army did not materialise in the summer of 1582. He again submitted in September 1582, but was generally mistrusted. During 1583–6 Fiach changed his policy towards the government and remained outwardly loyal. On the arrival of Sir John Perrot (qv) as lord deputy (June 1584), Fiach promised to acknowledge the courts, and delivered his pledges. Fiach's good intentions were demonstated by the holding of the sessions of the southern assize court at Ballinacor (September 1584). At the sessions, he presented vociferous complaints against the excesses of the seneschals. However, in November 1584 he and Harrington arrested and executed some cattle raiders. To Harrington's surprise, Fiach surrendered his son for collusion with the deceased. Fiach's reformation seemed complete when as an observer he attended Perrot's parliament (April 1585).
Despite this display, Fiach could not overcome the scepticism voiced by many officials. The evidence shows that he needed government protection. Since his grandfather's time, the Butlers were intent on recovering lands lost centuries earlier to the O'Byrnes. Also during the 1580s fissures within the ruling dynasty of Crioch Raghnuill finally opened. In April 1584 Ormond detached Aodh Dubh O'Byrne of Knockrath from Fiach by appointing him constable of Arklow. Ormond also encouraged the sons of Fiach's erstwhile rival, Sir Edmund Butler, to reestablish a land corridor between Arklow and Tullow. An alarmed Fiach increased his cooperation with Perrot in the hope of halting Ormond's ambitions. Despite the outbreak of war between England and Spain (August 1585), Fiach remained loyal. However, his budding links with the Ulstermen were exposed when his son escaped with Art O'Neill from Dublin castle during Christmas 1585. Fiach presented another son as a pledge, but his role in the affair was uncovered when his wife Rose and his brother were captured while escorting O'Neill back to Ulster. In April 1586 Perrot chose to overlook this and asked for permission to bring Fiach to court. This plan came to nothing. In May 1586 Fiach surprised government officials when he presented himself, dressed as an English noble. He was granted a pardon for himself, his wife and sons, and some followers. Throughout the summer Fiach sent in heads of malefactors, some of whom were his lesser-known rivals, to a delighted Perrot. Other officials were convinced Fiach was playing a double game.
By August 1586 Fiach was desperate. Perrot and the local government officials could not and would not stop the Butler advance. Disillusioned, Fiach returned to his old role of arch-plotter. To shore up his southern frontier, Fiach married his daughter Mairghréag to Walter Reagh FitzGerald (c. summer 1586). With Butler strength daily growing, Fiach ordered Walter Reagh and Conall O'More to attack them in August 1586, while he attacked their Kavanagh allies. When asked to come to Dublin and explain himself, he declined, but officially remained at peace. The struggle climaxed when Walter Reagh killed the constable of Leighlinbridge, Dudley Bagenal, in an ambush (21 March 1587), and – probably on Fiach's orders – fled northwards. English intelligence informed Perrot that O'Byrne was again in contact with the Spanish. A plot was formulated by Perrot and Tadhg O'Nolan to lure Fiach and his eldest son, Toirdhealbhach, into an ambush by Harrington and Sir William Collier. When this failed, O'Nolan offered to poison him. Perrot later wrote that Fiach refused to answer summons throughout 1587–8, because he was preparing for a Spanish landing in Ireland. According to Perrot's deposition, he alienated Tadhg O'Connor Faly from Fiach and incited Feilim O'Toole of Powerscourt and Aodh Dubh O'Byrne to attack him in summer 1588. This coincided with the reemergence of Fiach's feud with Harrington. In September 1588 Fiach and his son Toirdhealbhach established their suzerainty over the mountains. During a parley with his brother-in-law, Feilim O'Toole (qv) (d. 1603) of Powerscout, Fiach tried to kill him; O'Toole managed to escape, but Toirdhealbhach forcibly ensured Feilim's loyalty in winter 1588. Fiach's hardening attitude was displayed in the escape of his pledges from Dublin castle (25 February 1589) and his attacks on Ormond's constable of Arklow, Aodh Dubh. He burnt Aodh Dubh's lands and kidnapped his wife in March 1589. In October 1589 he threatened to storm Arklow unless Aodh Dubh was surrendered to him. By 1590 Fiach was again dominant within the region.
Alliances, 1590–95 Fiach continued to seek allies throughout Ireland. In 1590 he joined with Feriagh O'Kelly of Roscommon, and in nearby Longford Fergus O'Farrell dispatched his son Hubert to negotiate an alliance with Fiach. He planned the escape of Red Hugh (Aodh Ruadh) O'Donnell (qv) from Dublin castle. O'Donnell reached Castlekevin, where Fiach's wife Rose convinced her brother Feilim to hold him prisoner until Fiach's arrival. The flooding of the Avonmore prevented Fiach from reaching O'Donnell before the English. Fiach and his new ally Hugh O'Neill (qv), 2nd earl of Tyrone, orchestrated O'Donnell's second escape with the sons of Shane O'Neill (qv) on 6 January 1592. According to the deposition of James FitzGerald (1595), O'Donnell allied with Fiach before his return to Donegal. On Tyrone's wish, Fiach seemingly had Art O'Neill murdered. Fiach's actions confirmed him as a major constituent in Tyrone's catholic confederacy of Irish and Anglo-Irish nobles.
In 1593 Archbishop James O'Hely of Tuam brought Fiach's fervent catholicism and strategic position on the Pale's borders to the attention of Philip II of Spain. As the conspiracy mounted, Fiach dispatched Feriagh O'Kelly to aid Hugh Maguire (qv) in Fermanagh. Throughout the winter of 1593, Fiach disclaimed any involvement in his lieutenants’ attacks throughout Leinster. A turning-point came when his sons and Walter Reagh killed Sir Piers FitzGerald and his family on 18 March 1594. Fiach denied any connection to the outrage, but nobody believed him, least of all the lord deputy, William Fitzwilliam (qv). English intelligence reports and Irish poetry record that a Spanish military mission arrived in Glenmalure during May 1594. This caused consternation in government circles. Other reports and later evidence confirm that Fiach had supplies of food and gunpowder hidden throughout his lordship, and had ordered his axemen and blacksmiths to make a large quantity of pikes. The government acted quickly and martial law was declared in Leinster (15 August 1594).
Fiach's reaction was to unleash Ruaidhrí's son Uaithne O'More (qv) (d. 1600) and Piers Grace on the midlands. In October 1594 he ordered the mobilisation of males between 16 and 60 within Crioch Raghnuill. The lord deputy, William Russell (qv), realised the danger and drove Fiach from Ballinacor on 16 January 1595. Despite a successful raid on Crumlin (late January), Fiach's battle plans were disrupted. As a result of Russell's attack, Tyrone authorised his brother Art to take the Blackwater fort near Armagh. In a letter to the government, the earl asked for the cessation of Russell's offensive. In April 1595 Fiach suffered another blow when Walter Reagh was captured (7 April) and executed (10 April).
On 28 April 1595 soldiers captured Rose O'Toole, and on 27 May she was sentenced to be burned. Her capture opened up cracks within Fiach's family. Rose had no recorded children by Fiach, but her two sisters married to Fiach's younger sons had. Toirdhealbhach, Fiach's heir, was seemingly hated by his brothers and their O'Toole wives. In November 1595 government correspondence alleged that Rose intended to destroy Toirdhealbhach and thus procure Crioch Raghnuill on Fiach's death for her sisters’ husbands. The hatred between Rose and Toirdhealbhach was confirmed by the absence of his signature from the now lost marriage contract of Rose and Fiach. In a very unclear incident, Rose, while awaiting execution, was seemingly convinced that Toirdhealbhach intended to betray his father to Russell. Through her contacts she managed to convey a message to Fiach. He, fearful for his wife and concerned by her news, confronted his son, who denied all knowledge of a plot. Despite Toirdhealbhach's denial, Fiach arrested him. On 7 June 1595 he wrote asking for pardon for himself, his wife, and his followers, and promised to deliver Toirdhealbhach and Maurice FitzGerald to the government. And on 16 June he sent his son and FitzGerald to Dublin. There government officials asked Toirdhealbhach to kill Fiach; his refusal ensured his execution on 18 July. After her stepson's execution, Rose was quietly released and returned to her husband. Through the boasts of government officials, Fiach learned of the details of Toirdhealbhach's confinement. Shaken by his tragic mistake, he shook off advancing years and illness to relay foundations for war in 1596.
Fiach gained a chance to reorganise his forces by Tyrone's entry into the war (May 1595) and divisions between Russell and Sir John Norris (qv). In October 1595 negotiations began between Tyrone and Norris. This cessation allowed Fiach to submit in November. He was granted protection for three months. In April 1596 he petitioned Lord Burghley to speed his pardon and asked for the grant by letters patent of his estates. Fiach used his reprieve to cement old alliances and forge new ones. Ironically, he managed to draw the sons of his old rival Sir Edmund into alliance with him, which was sealed by the marriage of his niece Doireann, daughter of Ruaidhrí O'More, to James Butler (summer 1596).
War to the death, 1596–7 The wars of Fiach's lieutenants throughout east Leinster and the midlands infuriated the government, who were unable to take action against Fiach as he had done nothing openly. A parley was arranged between Fiach and the local army commander in late July. As Fiach arrived at the meeting, the cavalry charged; he escaped with difficulty. The tension increased in Leinster as officials became worried by the size of Fiach's forces. His new force and James Butler twice probed Ballinacor's defences (August), but Fiach denied any involvement and blamed the attack on strangers. Even Russell admired his guile and famously commented that Fiach had greater ability than Tyrone.
On 9 September 1596 Fiach took Ballinacor. Tyrone encouraged Fiach's recapture of Ballinacor to coincide with the expected arrival of a Spanish armada (Fiach was to open a second front against the government in preparation for the landing; but the armada was wrecked by storms in October 1596). In September 1596 Russell, with the support of many O'Byrnes, began a war to the death with Fiach. Fiach wrote to Brian Riabhach O'More (qv) (sl. 1598) and others and urged them to fight for their faith (November 1596). However, the misery caused by the Leinster war caused many to call for its cessation. In Leinster it dragged into 1597, and even though Fiach had suffered losses, he still offered stout resistance. In January 1597 Tyrone concluded a peace with Sir John Norris. Despite Tyrone's demands that Fiach be pardoned, and despite the misery of the Pale, the mountain war raged on. The mood for peace among the citizens of Dublin increased when ammunition exploded and destroyed much of the city on 13 March. On 30 April Norris advised Burghley of Tyrone's request that Fiach be pardoned.
This came too late for Fiach. His whereabouts were disclosed to Russell by a relative. Early on Sunday 8 May 1597 Russell's forces, under the command of Capt. Thomas Lee (qv), surrounded a house on Fananierin mountain. Fiach managed to hack his way out of the encircling ring, but his bodyguards were killed. Finding himself closely pursued and short of breath, he hid in a cave near a place called Manning's bog, but was spotted by Sgt Milburne, who had him dragged from the cave and beheaded. Russell celebrated by knighting three of his commanders, while Fiach's head and quarters were exhibited in Dublin; the head was later presented to Queen Elizabeth.