Oliver Plunkett, the Archbishop of Armagh in Ireland, was executed at Tyborn in London on July 1, 1681. He was the last priest to be executed there and the final victim of the "Popish Plot"--that fraudulent, perjured plot cooked up by the BBC's Worst Briton of the 17th Century: Titus Oates.
So in the Catholic dioceses of England and Wales AND Ireland, today is the memorial/feast of St. Oliver Plunkett, Archbishop of Armagh, victim of Stuart injustice during the Anti-Catholic madness of Oates' fake plot.
The Whigs in Parliament, opposed most of all to the succession of Charles II's Catholic brother, James the Duke of York, jumped at the opportunity to attack Catholics--and James--when Titus Oates fabricated the story of a great conspiracy. Charles II did not believe most of the elements of the plot Oates "revealed", especially when the perjuror implicated his own queen, Catherine of Braganza, and his brother.
Once Oates was able to compound English fear of Jesuits and Catholics with English fear of Irish Catholics, Plunkett was in grave danger. St. Oliver Plunkett was brought to London from Ireland and accused of conspiring to bring French soldiers and recruit members of his diocese to mount a rebellion against the King and Parliament. There was, of course, no evidence of these accusations and Plunkett could bring no witnesses to testify for him--they were in Ireland and not permitted to come to England. He had been tried before in Ireland--no double jeopardy applied here--and English authorities like Shaftesbury were convinced that no Irish jury (even if packed with Protestants) would convict him.
On the day of his execution he was able to give a long discourse, in which he re-presented the evidence that proved he was not involved in any conspiracy, and which concluded with forgiveness and prayers:
as one of the said deacons (to wit, holy Stephen) did pray for those who stoned him to death; so do I, for those who, with perjuries, spill my innocent blood; saying, as St. Stephen did, "O Lord! lay not this sin to them." I do heartily forgive them, and also the judges, who, by denying me sufficient time to bring my records and witnesses from Ireland, did expose my life to evident danger. I do also forgive all those, who had a hand, in bringing me from Ireland, to be tried here; where it was morally impossible for me to have a fair trial. I do finally forgive all who did concur, directly or indirectly, to take away my life; and I ask forgiveness of all those whom I ever offended by thought, word, or deed.
I beseech the All-powerful, that his Divine Majesty grant our king, queen, and the duke of York, and all the royal family, health, long life, and all prosperity in this world and in the next, everlasting felicity.
Now, that 1 have shewed sufficiently (as I think) how innocent I am of any plot or conspiracy: I would I were able, with the like truth, to clear myself of high crimes committed against the Divine Majesty's commandments, often transgressed by me, for which, I am sorry with all my heart; and if I should or could live a thousand years, I have a firm resolution, and a strong purpose, by your grace, O my God! never to offend you; and I beseech your Divine Majesty, by the merits of Christ, and by the intercession of his Blessed Mother, and all the holy angels and saints, to forgive me my sins, and to grant my soul eternal rest. Miserere mei Deus, etc. Parce anima, etc. In manus tuas, etc.
St. Oliver Plunkett was born in 1629 in Loughcrew, County Meath, Ireland of well-to-do parents and studied for the priesthood at the Irish College in Rome. While Oliver Cromwell was inflicting the "righteous judgement of God" on the Irish who had rebelled against English rule during Charles I's reign, Plunkett had been unable to return to serve his people as a priest after ordination in 1654. He therefore remained in Rome and taught theology. In 1669 he was appointed the Archbishop of Armagh and the Primate of All Ireland and finally returned to Ireland the next year. For a time, Charles II's Restoration leniency allowed Plunkett to accomplish many reforms and reorganizations in education and catechesis. As Archbishop, he confirmed thousands (48,000!) but in 1673, persecution of Catholics in England's colony forced him to go into hiding and close the schools. Arrested in connection with Oates' plot, he was imprisoned at Dublin Castle. He was canonized by Pope Paul VI in 1975 and in 1997 he was named the Patron Saint of Peace and Reconciliation in Ireland. His trial and execution were so manifestly unfair that even Shaftesbury realized things had gone too far--yet, with the Popish Plot's true conspirators, Oates and companions, finally being mistrusted and the whole matter winding down, Charles II did nothing to stop the execution of St. Oliver Plunkett. This site contains a wealth of information, including the prayers and readings for a Mass honoring his Feast.