By 1578, the English plantation of Laois and Offaly in Leinster was in full swing. The local Gaelic opposition to the new order had faded away following the death of Ruaidhrí Óg O’More in June that year. However, there was one area in Leinster that remained largely Gaelic. Ironically, this was also the Gaelic area geographically closest to Dublin, by now the heart of the English administration in Ireland. The mountainous area of the county today known as Wicklow, as well as the neighbouring parts of Carlow and Wexford, were still Gaelic heartlands. The ‘surrender and regrant’ scheme had entirely failed in this part of Leinster. The lands were too mountainous and inaccessible to form part of the earlier Plantation of Leinster, and it was too small for the presidency models that had been adopted in Munster in 1566 and Connaught in 1569. It was dominated by Gaelic families such as the Kavanaghs and O’Tooles, but most of the lands were controlled by the O’Byrnes, so much so that a large part of what we today call Wicklow was still known as ‘O’Byrnes country’ in 1580. It was from a relatively junior branch of the O’Byrnes that a new leader came to the fore, one who would unite the remaining Gaelic families in Leinster to resist the Tudor English government.

Feagh McHugh O’Byrne was born during the 1540s. Little is known about his early life, but in time he became chief of the Gabhal Raghnaill, a junior branch of the notorious O’Byrnes of Wicklow. Feagh had already earned a fierce reputation by the time he succeeded his father as chief of the family in 1579. Indeed, for many years previous he was regarded by the Dublin authorities as de facto chief of his family. He had also begun to make alliances with the other Gaelic families in Leinster. For example, Feagh himself was married to Rose O’Toole, the daughter of the O’Toole chief who ruled the area around Glendalough in the heart of the Wicklow Mountains. His sister Isabel was married to Phelim O’Toole, another powerful family who held lands at Powerscourt, within only 25km from Dublin itself. His other sister, Margaret Maol, was married to Ruaidhrí Óg O’More of Laois. 

In the aftermath of the death of his brother-in-law, Ruaidhrí Óg O’More, in June 1578, Feagh McHugh O’Byrne realised that he was in a very isolated position. He had seen the treatment of the O’Mores in Laois and knew that it was only a matter of time before English eyes would cast their gaze towards Wicklow. Therefore, in order to buy more time for himself, he made the pragmatic decision to submit to the lord justice, William Drury (former president of Munster) at Christ Church on 21st September, 1578, and swore to keep the peace.

However, as we have seen in the case of Gerald fitzGerald, the 15th earl of Desmond, it was not simply the Gaelic families who resisted the new English government in Ireland. Some of the ‘old’ English families of the Dublin region, known as the Pale, had become increasingly resentful of the ‘new’ English administration in Ireland. They had been asked to carry much of the burden of the military tax, known as the cess, that had been introduced by the lord deputy, Sir Henry Sidney, to pay for the military garrisons established in the plantation of Laois and Offaly. In addition, the government administration in Ireland was becoming increasingly staffed by a new generation of English arrivals to Ireland. Added to the mix were religious differences. The recent English arrivals, including the newly appointed government officials and administrators, were all Protestant, whereas the old English families of the Pale were conservative Catholics who had resisted the changes brought in by the Reformation. One of the main voices from the Pale who agitated against the government was Roland fitzEustace, 2nd viscount Baltinglass. His father, Thomas, had been granted the title of viscount Baltinglass by Henry VIII in 1541 and was granted the recently dissolved Cistercian abbey at Baltinglass in southwest Wicklow, which had been founded by Diarmaid Mac Murchadha in 1148. It is said that Thomas provided shelter to the displaced monks from the abbey. Closer to the family seat in Kilcullen, Co. Kildare, Thomas also acquired the lands of the ‘New Abbey’ overlooking the River Liffey. Dissolved in 1539, it was known as the ‘New Abbey’ because it had been founded as recently as 1486 by Roland fitzEustace, baron Portlester, who was complicit with Gerald fitzGerald, 8th earl of Kildare, during the coronation of Lambert Simnel in Christ Church in 1487, only a year after the foundation of the abbey. It was, in fact, a Franciscan friary, and with its closure, the lands simply reverted to Thomas fitzEustace, whose favour with the king was in part due to his support against the rebellion of ‘Silken’ Thomas fitzGerald in 1534. Ultimately, Roland was torn between following his Catholic faith and remaining loyal to the queen. Rather than using militant aggression to agitate against the cess, Roland fitzEustace had used legal and diplomatic measures to make his case. However, his son, James, felt no such allegiance to the crown at the expense of his Catholic beliefs.

At 28 years of age, James fitzEustace became 3rd viscount Baltinglass in 1579 after the death of his father. A few years previously, James had traveled to Rome, where he witnessed first-hand the emergence of the Counter-Reformation in Catholic Europe. Here, he was strongly influenced by a small but energetic group of English and Irish Catholics who were plotting the overthrow of queen Elizabeth and her Protestant government. James returned to Ireland in 1578 and quickly came to the attention of the English administration in Dublin for his blatant expressions of Catholicism. Not content with simply wishing to openly express his faith, James quickly set about looking for others who would take a militant stand. He found some support among the gentry of the Pale, who were predominantly ‘old’ English and had retained their Catholic faith. However, many leading families declined to support his cause; they still had vivid memories of the failed rebellion of ‘Silken’ Thomas fitzGerald in 1534. Therefore, in order to broaden his alliances, he looked to his Gaelic neighbours in Leinster. The man he approached for help was Feagh McHugh O’Byrne.

James fitzEustace was married to Mary Travers, whose father, John, had come to Ireland from Cornwall as master of the king’s ordnance and in 1539 had acquired the lands known as Monkstown outside the city, which had been a farm or grange belonging to the recently dissolved St Mary’s Abbey in Dublin. During Easter week 1580, James fitzEustace convened a three-day meeting at his wife’s home at Monkstown Castle, on the outskirts of Dublin. In attendance was a small, select group of Pale gentry who were sympathetic to his cause, as well as Feagh McHugh O’Byrne. Also at the meeting was a militant Wexford priest, Father Robert Rochford, who had acted as a messenger between James fitzEustace and James fitzMaurice fitzGerald, after the latter landed in Kerry in July 1579. At that time, fitzEustace was not prepared to act. Now, James and Feagh wrote to the leaders in Munster declaring their intention to join them. What followed has become known as the Baltinglass Rebellion. At its core, the objectives of this Leinster revolt mirrored those in Munster; the restoration of the Catholic faith and the overthrow of queen Elizabeth.

In the weeks that followed the Easter meeting at Monkstown, James continued to seek support from the Anglo-Irish gentry of the Pale. As a result, the government soon became aware of his plans. Feagh returned to Wicklow and quickly began to seek the support of the Gaelic families in Leinster. However, with the O’Mores and O’Connors of Laois and Offaly weakened by the military actions of the plantations in west Leinster, Feagh’s options were limited to the Kavanaghs, O’Tooles, and the other branches of the O’Byrnes in east Leinster. On 28th July, Feagh went on the offensive and with a large force attacked Newcastle MacKinegan in east Wicklow, where he hung the Papal banner over the castle gate. The castle was then owned by Sir Henry Harrington, who had been kidnapped by Ruaidhrí Óg O’More a few years earlier. The decision to attack Harrington’s castle was highly symbolic. Harrington had been recently appointed seneschal of the ‘O’Byrnes country’. The office of seneschal was effectively the most senior government post in the area, giving Harrington full judicial powers over the O’Byrnes. Indeed, Feagh had agreed to recognise Harrington’s authority when he submitted to William Drury at Christ Church in September 1578. Therefore, by attacking Harrington’s castle, Feagh was now rejecting his earlier agreement and striking at the very heart of the English government’s administration over the ‘O’Byrne’s country’. The Baltinglass Rebellion had now officially begun.

On 12th August, 1580, Arthur Grey, Baron of Wilton, arrived in Dublin as the new lord deputy, disembarking from a ship called Handmaid. He brought with him a large force of soldiers to quash the revolts in Leinster and Munster. He had limited military experience, and certainly had never undertaken a military campaign in Ireland before. On his arrival, James fitzEustace and his allies withdrew to Feagh’s stronghold in the valley of Glenmalure deep within the Wicklow mountains. 

On 25th August, Grey marched into the valley, with some 2000 men, including hired Gaelic soldiers from Connaught. They more than doubled the combined forces of James fitzEustace and Feagh McHugh. As the army entered the valley and confident in his numerical superiority, Grey was intent on a direct assault. The retreating rebels lured Grey’s army deeper into the valley. Here the rebels were concealed in the wooded slopes of the valley and were able to pick-off the advancing army one-by-one. They used the steep slopes to pin down the English army at the bottom of the valley. Their scarlet and blue coats made them easy targets. Eventually, the panicked soldiers fled, and Grey withdrew the rest of his army in disgrace. Among the dead was Francis Cosby, who had taken part in the massacre of the O’Mores at Mullamast in March 1578. Among those who witnessed the defeat was Sir Nicholas Malby, president of Connaught, as well as the renowned English poet Edmund Spenser and a certain captain Walter Raleigh (years later, both Spenser and Raleigh would become central figures in the English plantation of Munster). This was a famous victory for Feagh McHugh and viscount Baltinglass and eclipsed any successes that the Desmond rebellion had achieved in Munster.

Indeed, among those who witnessed this famous victory at Glenmalure were Dr Nicholas Sanders, the papal envoy, and John fitzGerald, brother of the earl Desmond, who had traveled to Wicklow to confer with Feagh and James on how best to link the revolt in Leinster with the Desmond Rebellion in Munster. While they were in Wicklow, they received news of the arrival of Italian and Spanish troops at Smerwick in Kerry. In early October they decided to swiftly return to Munster. Remarkably, James fitzEustace decided to join them, taking with him a large part of the Leinster rebels. In so doing, the man who had initiated and given his name to the Baltinglass Rebellion now undermined it.

With James fitzEustace gone to Kerry, it fell onto Feagh MacHugh to lead the rebellion in Leinster. He soon found himself isolated in the Wicklow Mountains. The government forces would not repeat the mistake they had made by fighting Feagh on his home ground, and Feagh simply did not have the military resources in terms of troops or heavy artillery to engage in any effective combat outside the rugged slopes of Glenmalure. In the short-term, however, the arrival of Italian and Spanish troops in Kerry took the limelight away from Feagh. Even though the number of troops was relatively small, the presence of troops representing foreign sovereigns, as well as the pope, was a threat that needed to be dealt with immediately. With the defeat at Glenmalure still fresh in his mind, Grey made arrangements for the siege of Dún an Óir in Kerry in November, where his reputation would be restored. With a large contingent of crown forces headed for Munster, the government opted to contain Feagh within the Wicklow mountains by establishing garrisons around the foothills.

In April 1581, when the crown forces decided to enter the valley of Glenmalure once again, there would be no repeat of his earlier victory. The unopposed soldiers burnt Feagh’s castle to the ground. In July, two hundred of his Kavanagh allies in north Wexford were slaughtered by Thomas Masterson, constable of Ferns Castle, in a scene that was reminiscent of the massacre of the O’More’s at Mullamast in 1578. On 28th August 1581, almost exactly a year after the Battle of Glenmalure, Feagh agreed to cease hostilities, and the government issued a pardon. James fitzEustace, viscount Baltinglass, on the other hand, refused to submit and evaded capture. He subsequently went to Ulster from where he escaped to Scotland, before making his way to Spain. Here he hoped to recruit military support to bring back to Ireland, but he never returned. After his submission, Feagh waited for assistance from fitzEustace, but it never arrived. The so-called Baltinglass Rebellion in Leinster had collapsed long before the death of the earl of Desmond in November 1583 that brought an end to the Desmond Rebellion in Munster. By appealing to continental sovereigns to intervene in Irish affairs, the Leinster and Munster revolts had posed the most serious threat to English rule in Ireland since arrival of Edward Bruce in 1315. They would prove to be a precursor of an even greater threat still to come.