Saint Oliver Plunkett was the last Roman Catholic Martyr to die in England. He was canonized in 1975, the first new Irish saint in almost 700 years.

Oliver was born in Loughcrew, Oldcastle, County Meath in November 1625, the son of the Baron of Loughcrew. As a young man, he wanted to become a priest, but it was illegal to travel to the continent to enter seminary. Even so, he undertook the dangerous journey with four other young men and a Papal Envoy. They were pursued by English privateers, storms at sea, and robbers on land. However, Oliver entered Rome in 1647, and was admitted to the Irish College. He was an excellent student and was ordained on January 1, 1654. Oliver remained in Rome, studied law and served as chaplain at Spienza University, ministered at Santo Spirito hospital, and cared for the poor and ill. By 1657 he was a professor of Theology and later of Apologetics or Controversies at Propaganda College.

The 1650s were a difficult time in for Catholics in Ireland, the majority of population, as Cromwell passed many penal laws against them, and the practice of Catholicism was banned. During this time Oliver was appointed by Irish bishops to be their agent in Rome. Following the Restoration of Monarchy, Pope Clement IX appointed Oliver Archbishop of Armagh and Primate of all Ireland 1669. Oliver returned to a country where the Catholic Church was in disarray and divided. He had to travel largely incognito and perform his duties in makeshift locations. He is credited with unifying the Church and in traveling across the eleven dioceses under his purview, confirming thousands, and ordaining several priests.

In 1673 persecution of Catholics was again on the rise and bishops were banned. Oliver went into hiding, but in 1679 he was arrested and charged with treason. He was hanged, drawn, and quartered at Tyburn in July 1681. Before his death he publicly forgave those responsible.