Alongside his older brother, Connor Maguire, Maguire is a prime mover in the conspiracy which leads to the outbreak of rebellion in Ireland on October 23, 1641. He is tasked with securing County Fermanagh for the rebels, but is only partially successful, with several key fortresses in the county, including Enniskillen Castle, remaining under Protestant settler control. His attempt to murder Sir William Cole immediately prior to the rising fails, but the landowner Arthur Champion is killed in one of the first actions of the rebellion. In November 1641, he joins Felim O’Neill of Kinard at Newry to issue a proclamation in which the rebels claim they are acting in defence of King Charles and Catholicism. In December 1641, the Fermanagh army under Maguire slaughters many of the garrison and refugees in Tully Castle, apparently in retaliation for the killing of the garrison of a Maguire castle which had been taken by assault some days previously. He also destroys Castle Archdale and its neighbouring settler village, and kills eight Protestant settlers at Monea Castle. In early 1642, he is expelled from the Irish Parliament and in the summer of the same year he is made a colonel in Owen Roe O’Neill‘s army in Ulster.
Maguire is appointed Governor of Fermanagh by the authorities of the newly established Confederate Ireland. He commands the rebel reserve in the Battle of Benburb in June 1646. He leads raids into Protestant-held areas in east Ulster, before joining O’Neill in his campaigns in Leinster in the autumn of 1646. Later that year, he raids lands in Connacht controlled by the Royalist commander, Ulick Burke, 1st Marquess of Clanricarde. In August 1647, O’Neill and Maguire move the army to Leinster, where Maguire quarrels so vigorously with O’Neill over the payment of troops that the general orders his arrest and court-martials him. After the court-martial, Maguire and his supporters, about five or six regiments, draw up their forces and threaten to desert. The mutiny soon dissipates and Maguire remains allied to O’Neill.
In 1648, Maguire joins O’Neill in opposing the truce between the Confederates and Royalists. He plays a prominent role in the skirmishes and evasive manoeuvrings that occur between the two sides in central Ireland. In the winter of 1648, Maguire withdraws north and on November 13 he is killed while leading an attack on a fortress near Jamestown, County Leitrim.
Sir Rory O’Moore (Irish: Ruaidhrí Ó Mórdha), Irish politician and landowner also known Sir Roger O’Moore or O’More or Sir Roger Moore, dies in obscurity on February 16, 1655. He is most notable for being one of the four principal organizers of the Irish Rebellion of 1641.
O’Moore’s uncle, Rory O’More, Lord of Laois, had fought against the English during the Tudor conquest of Ireland. In 1556, Queen Mary I confiscates the O’Mores’ lands and creates “Queens County” (modern-day County Laois). Over 180 family members, who are peaceful and have taken no part in any rebellion, are murdered with virtually all of the leaders of Laois and Offaly by the English at a feast at Mullaghmast, County Kildare, in 1577. Rory Óg and his wife Maighréad O’Byrne, sister of Fiach MacHugh O’Byrne, are hunted down and killed soon afterwards. This leads to the political downfall of the O’Moore family as their estates are given to English settlers.
Given the causes of the rebellion and the Crown’s weakness during the Bishops’ Wars into 1641, O’Moore plans a bloodless coup to overthrow the English government in Ireland. With Connor Maguire, 2nd Baron of Enniskillen, he plans to seize Dublin Castle, which is held by a small garrison, on October 23, 1641. Allies in Ulster led by Sir Phelim O’Neill are to seize forts and towns there. The leaders are to assume the governing of their own country and with this provision offer allegiance to King Charles. They are betrayed, and the plan is discovered on October 22 and the rising fails in its first objective. O’Neill has some success, and O’Moore quickly succeeds in creating an alliance between the Ulster Gaelic clans and the Old English gentry in Leinster.
In November 1641, the Irish forces besiege Drogheda, and a royalist force comes north from Dublin to oppose them. O’Moore is one of the leaders of the rebel army that intercepts and defeats the relief force at the Battle of Julianstown on November 29.
The Irish historian Charles Gavan Duffy writes: “Then a private gentleman, with no resources beyond his intellect and his courage, this Rory, when Ireland was weakened by defeat and confiscation, and guarded with a jealous care constantly increasing in strictness and severity, conceived the vast design of rescuing the country from England, and even accomplished it; for, in three years, England did not retain a city in Ireland but Dublin and Drogheda, and for eight years the land was possessed and the supreme authority exercised by the Confederation created by O’Moore. History contains no stricter instance of the influence of an individual mind.”
Bishop Michael Comerford writes that after O’Moore’s defeat at the Battle of Kilrush in April 1642 he retires and dies in Kilkenny city in the winter of 1642–43, having co-founded the Irish Catholic Confederation there a few months earlier. However, this ignores his contacts with Inchiquin and Ormonde in 1647–48.
In 1652, O’Moore goes to Inishbofin off the coast of Galway, one of the last Catholic strongholds, but as the parliamentary forces approach, he makes arrangements to flee. Walter Lynch, Bishop of Clonfert, sails in the last ship to leave the island without waiting for O’Moore, who is forced to make his own way. He finally escapes into Ulster but dies in obscurity on February 16, 1655. He is buried at Steryne churchyard, in the parish of Magilligan, County Londonderry.
St. Colman’s Church on the island once bears a tablet with the inscription: “In memory of many valiant Irishmen who were exiled to this Holy Island and in particular Rory O’More a brave chieftain of Leix, who after fighting for Faith and Fatherland, disguised as a fisherman escaped from his island to a place of safety. He died shortly afterwards, a martyr to his Religion and his County, about 1653. He was esteemed and loved by his countrymen, who celebrated his many deeds of valour and kindness in their songs and reverenced his memory, so that it was a common expression among them; ‘God and Our Lady be our help and Rory O’More’.”
The Balyna estate is inherited from Calvagh O’More by Rory’s brother Lewis. Balyna is passed down to Lewis’s last surviving O’More descendant, Letitia, who is also descended from Rory O’More because her grandfather married a second cousin. Letitia marries a Richard Farrell in 1751. This Farrell family henceforth takes the surname More O’Ferrall.