Oliver Plunket was born on 1 November 1625 into an influential Anglo-Norman family at Loughcrew, near Oldcastle, Co Meath. In 1647, he went to the Irish College in Rome to study for the priesthood and was ordained a priest in 1654. The arrival of Cromwell in Ireland in 1649 initiated the massacre and persecution of Catholics. Cromwell left in 1650 but his legacy was enacted in anti-Catholic legislation. During the 1650s, Catholics were expelled from Dublin and landowners were dispossessed. Catholic priests were outlawed and those who continued to administer the sacraments were hanged or transported to the West Indies. To avoid persecution, Plunket petitioned to remain in Rome, and in 1657 became a professor of theology.

When anti-Catholicism eased, Plunket returned to Ireland. In 1657 he became archbishop of Armagh. He set about reorganizing the ravaged Church, and built schools both for the young and for clergy whom he found 'ignorant in moral theology and controversies'. He tackled drunkenness among the clergy, writing 'Let us remove this defect from an Irish priest, and he will be a saint.'

In 1670, he summoned an episcopal conference in Dublin, and later held numerous synods in his own arch diocese. However, he had a long standing difference with the archbishop of Dublin, Peter Talbot, over their rival claims to be primate of Ireland. He also antagonized the Franciscans, particularly when he favored the Dominicans in a property dispute.

With the onset of new persecution in 1673, Plunket went into hiding, refusing a government edict to register at a seaport and await passage into exile. In 1678, the so-called Popish Plot concocted in England by Titus Oates led to further anti-Catholicism. Archbishop Talbot was arrested, and Plunket again went into hiding. The privy council in London was told he had plotted a French invasion.

In December 1679, Plunket was imprisoned in Dublin Castle, where he gave absolution to the dying Talbot. Taken to London, he was found guilty in June 1681 of high treason on perjured evidence from two disaffected Franciscans. On 1 July 1681, Plunket became the last Catholic martyr in England when he was hanged, drawn and quartered at Tyburn. He was beatified in 1920 and canonized in 1975, the first new Irish saint for almost seven hundred years.

—Excerpted from Irelandseye.com and contributors

This account was taken from Bishop Burnet's, History of his own Time, 1724:

Dr. Oliver Plunket was. arraigned at the King's Bench, May 3, 1681, for "high treason, in endeavoring and compassing the king's" death, and to levy war in Ireland, and to alter the true religion there, and to introduce a foreign 'power.' The particulars of his trial, as well as his speech at the place of execution, may be found in the third volume of the State Trials, p. 294, Margrave's edit. Dr. Burnet gives us no very favorable idea of the equity of the proceedings against him. ' Some lewd Irish priests (says he) and others of that nation, ' hearing that England was at that time disposed to hearken to good swearers, thought themselves well qualified for the employment; so they came over to swear, that there was a great plot in Ireland, to bring over a French army, and to massacre all the English. The witnesses were brutal and profligate men, yet the earl of Shaftsbury cherished them much: they were examined by the parliament at Westminster and what they said was believed. Upon that encouragement it was reckoned, that we should have witnesses come over in whole companies. Lord Essex told me, that this Plunket was a wise and sober man, who was always in a different interest from the two Talbots; the one of these being the titular primate of Dublin, and the other came to be raised afterwards to be Duke of Tirconnell. These were meddling and factious men, whereas Plunket was for their living quietly, and in due submission to the government, without engaging into intrigues of state. Some of these priests had been censured by him for their lewdness: and they drew others to swear as they directed them. They had appeared the winter before, upon a bill offered to the grand jury: but as the foreman of the jury, who was a zealous Protestant, told me, they contradicted one another so evidently, that they would not find the bill. But now they laid their story better together and swore against Plunket, that he had got a great bank of money to be prepared, and that he had an army listed, and was in a correspondence with Franco, to bring over a fleet from thence. He had nothing to say in his own defense, but to deny all: so he was condemned; and suffered very decently, expressing himself in many particulars as became a bishop. He died denying every thing that had been sworn against him.

The following account of the manner of his execution is given in a little work, entitled, Ireland's Case: briefly stated; or a summary Account of the most remarkable Transactions in that Kingdom, since the Reformation. 1675.

On the first of July 1681, Mr. Sheriff demanded his prisoner, who was carried to him on a sledge to be hanged, drawn, and quartered. In his passage to the place of execution, he made many ejaculatory prayers, full of the love of God, and charity to his neighbors. When he arrived at Tyburn, and was tied up, before the cart was drawn from under him, he made with wonderful cheerfulness this following: 'discourse.'

His speech ended, and his cap drawn over his eyes, he again recommended his happy soul with raptures of devotion into the hands of Jesus, his Savior, for whose sake he died, till the cart was drawn from under him. Thus then he hung betwixt heaven and earth, an open sacrifice to God for innocence and religion. As soon.as he expired, the executioner ripped up his belly and breast, and pulling out his heart and bowels, threw them into the fire, ready kindled near the gallows for that purpose: the rest of his body, having been begged of the king, was carried by his friends to a house near St. Giles's church; the trunk, whereof was placed in a coffin, his head and arms to the elbow, being reserved out of the coffin, and disposed of elsewhere; then the body was interred in the church.yard, and a copper plate placed on his breast, whereon was engraven these following words, set here down for the satisfaction of the curious: "In this tomb resteth the body of the right reverend Oliver Plunket, archbishop of Armagh, and primate of Ireland, who in hatred of religion was accused of false witnesses, and for the same condemned, and executed at Tyburn; his heart and bowels being taken out and cast into the fire: he suffered martyrdom with constancy, the 1st of July, 1681, in the reign of king, Charles II."

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