Owen Roe O’Neill, Gaelic Irish soldier and one of the most famous of the O’Neill dynasty of Ulster, dies on November 6, 1649 at the O’Reilly stronghold of Cloughoughter Castle located on an island in Lough Oughter in County Cavan.

O’Neill is the illegitimate son of Art MacBaron O’Neill, a younger brother of Hugh O’Neill, 2nd Earl of Tyrone, who holds lands in County Armagh. His mother is the daughter of Aodh Conallach O’Raghallaigh, the chief of Breifne O’Reilly in County Cavan.

As a young man O’Neill leaves Ireland, one of the ninety-nine involved in the Flight of the Earls escaping the English conquest of his native Ulster. He grows up in the Spanish Netherlands and spends 40 years serving in the Irish regiment of the Spanish army. He sees most of his combat in the Eighty Years’ War against the Dutch Republic in Flanders, notably at the Siege of Arras, where he commands the Spanish garrison. He also distinguishes himself in the Franco-Spanish War by holding out for 48 days with 2,000 men against a French army of 35,000.

O’Neill is, like many Gaelic Irish officers in the Spanish service, very hostile to the English Protestant presence in Ireland. In 1627, he is involved in petitioning the Spanish monarchy to invade Ireland using the Irish Spanish regiments. He proposes that Ireland be made a republic under Spanish protection to avoid in-fighting between Irish Catholic landed families over which of them would provide a prince or king of Ireland. This plot comes to nothing. However in 1642, He returns to Ireland with 300 veterans to aid the Irish Rebellion of 1641.

The subsequent war, known as the Irish Confederate Wars, is part of the Wars of the Three Kingdoms, civil wars throughout Britain and Ireland. Because of his military experience, O’Neill is recognised on his return to Ireland in July 1642, at Doe Castle in County Donegal, as the leading representative of the O’Neills and head of the Ulster Irish. Sir Phelim O’Neill resigns the northern command of the Irish rebellion in his favour and escorts him from Lough Swilly to Charlemont.

Jealousy between the kinsmen is complicated by differences between O’Neill and the Catholic Confederation which meet at Kilkenny in October 1642. O’Neill professes to be acting in the interest of Charles I, but his real aim is the complete Independence of Ireland as a Roman Catholic country, while the Old English Catholics represented by the council desire to secure religious liberty and an Irish constitution under the crown of England. More concretely, O’Neill wants the Plantation of Ulster overturned and the recovery of the O’Neill clan’s ancestral lands. Moreover, he is unhappy that the majority of Confederate military resources are directed to Thomas Preston‘s Leinster army. Preston is also a Spanish veteran but he and O’Neill have an intense personal dislike of each other.

Although O’Neill is a competent general, he is outnumbered by the Scottish Covenanter army that lands in Ulster in 1642. Following a reverse at Clones, he has to abandon central Ulster and is followed by thousands of refugees, fleeing the retribution of the Scottish soldiers for some atrocities against Protestants in the rebellion of 1641. He does his best to stop the killings of Protestant civilians, for which he receives the gratitude of many Protestant settlers. From 1642–1646 a stalemate exists in Ulster, which he uses to train and discipline his Ulster Army. This poorly supplied force nevertheless gains a very bad reputation for plundering and robbing friendly civilians around its quarters in northern Leinster and southern Ulster.

In 1646 O’Neill, with substantial Gallowglass numbers and additionally furnished with supplies by the Papal Nuncio, Giovanni Battista Rinuccini, attacks the Scottish Covenanter army under Major-General Robert Monro, who had landed in Ireland in April 1642. On June 5, 1646 O’Neill utterly routs Monro at the Battle of Benburb, killing or capturing up to 3,000 Scots. However after being summoned to the south by Rinuccini, he fails to take advantage of the victory, and allows Monro to remain unmolested at Carrickfergus.

In March 1646 a treaty is signed between James Butler, 1st Duke of Ormond and the Catholics, which would have committed the Catholics to sending troops to aid the Royalist cause in the English Civil War. The peace terms however, are rejected by a majority of the Irish Catholic military leaders and the Catholic clergy including the Nuncio, Rinuccini. O’Neill leads his Ulster army, along with Thomas Preston’s Leinster army, in a failed attempt to take Dublin from Ormond. However, the Irish Confederates suffer heavy military defeats the following year at the hands of Parliamentarian forces in Ireland at Dungan’s Hill and Knocknanauss, leading to a moderation of their demands and a new peace deal with the Royalists. This time O’Neill is alone among the Irish generals in rejecting the peace deal and finds himself isolated by the departure of the papal nuncio from Ireland in February 1649.

So alienated is O’Neill by the terms of the peace the Confederates have made with Ormond that he refuses to join the Catholic/Royalist coalition and in 1648 his Ulster army fights with other Irish Catholic armies. He makes overtures for alliance to George Monck, 1st Duke of Albemarle, who is in command of the parliamentarians in the north, to obtain supplies for his forces, and at one stage even tries to make a separate treaty with the English Parliament against the Royalists in Ireland. Failing to obtain any better terms from them, he turns once more to Ormond and the Catholic confederates, with whom he prepares to co-operate more earnestly when Oliver Cromwell‘s arrival in Ireland in August 1649 brings the Catholic party face to face with serious danger.

Before, however, anything is accomplished by this combination, O’Neill dies on November 6, 1649 at the O’Reilly stronghold of Cloughoughter Castle located on an island in Lough Oughter in County Cavan. There is no clear evidence of the cause of death, with one belief being that he was poisoned by a priest, while others think it is more likely that he died from an illness resulting from an old wound. Under cover of night he is reputed to have been brought to the Franciscan abbey in Cavan town for burial. However some local tradition still suggests that it may have been at Trinity abbey located upon an island in Lough Oughter, which may be more likely given the logistics of his removal. His death is a major blow to the Irish of Ulster and is kept secret for some time.

The Catholic nobles and gentry meet in Ulster in March 1650 to appoint a commander to succeed O’Neill, and their choice is Heber MacMahon, Roman Catholic Bishop of Clogher, the chief organiser of the recent Clonmacnoise meeting. O’Neill’s Ulster army is unable to prevent the Cromwellian conquest of Ireland, despite a successful defence of Clonmel by O’Neill’s nephew Hugh Dubh O’Neill and is destroyed at the Battle of Scarrifholis in County Donegal in 1650. Its remnants continue guerrilla warfare until 1653, when they surrender at Cloughoughter Castle in County Cavan. Most of the survivors are transported to serve in the Spanish Army.

In the nineteenth century, O’Neill is celebrated by the Irish nationalist revolutionaries, the Young Irelanders, who see him as an Irish patriot. Thomas Davis writes a famous song about O’Neill, titled “The Lament for Owen Roe” which is popularised in their newspaper, The Nation.

O’Neill has been commemorated in the names of several Gaelic Athletic Association clubs, including Middletown Eoghan Rua Gaelic Athletic Club in County Armagh; CLG Eoghan Rua in Coleraine; St. Oliver Plunketts/Eoghan Ruadh GAA in Dublin, and Brackaville Owen Roes GFC; Owen Roe O’Neill’s GAC in County Tyrone; and the defunct Benburb Eoghan Ruadh GAC.