Archbishop Paul Cullen, Roman Catholic Archbishop of Dublin and previously of Armagh, is elevated to the cardinalate as Cardinal-Priest of San Pietro in Montorio on June 22, 1866, becoming the first Irish cardinal.
Cullen is ordained in 1829 and is appointed Rector of the Pontifical Irish College in Rome in late 1831. He successfully secured the future of the college by increasing the student population and thereby strengthening the finances of the college.
Cullen is promoted to the primatial See of Armagh on December 19, 1849 and is consecrated by the Cardinal Prefect of Propaganda at the Irish College in Rome on February 24, 1850. He is also named Apostolic Delegate. Cullen is transferred to the See of Dublin on May 1, 1852.
Cullen is sent to Ireland to bring the Irish church into conformity with Roman canon law and usage. His first major act as Archbishop of Armagh is to convene the Synod of Thurles, the first national synod held in Ireland since the Reformation. This occurs during the period of the debilitating Irish Famine which reduces the population of the country by over 2 million people through starvation, disease, and emigration. After a series of disastrous harvests in the 1860s, he founds, along with the Lord Mayor of Dublin, the Mansion House Relief Committee in 1862. Cullen also starts the practice of Irish priests wearing Roman clerical collars and being called “Father” rather than “Mister” by their parishioners.
Cullen pays frequent visits to Rome. He takes part in the definition of the dogma of the Immaculate Conception of the Blessed Virgin Mary in 1854, and with the eighteenth centenary of the martyrdom of Saints Peter and Paul in 1867.
After his elevation to cardinal, Cardinal Cullen takes an active part in deliberations during the Vatican Council. Towards the close of the council at the express wish of the Central Commission, Cardinal Cullen proposes a formula for the definition of Papal Infallibility. It is a matter of great delicacy, as promoters of the definition are split up into various factions, some anxious to assign a wide range to the pope’s decisions, while others wish to set forth in a somewhat indefinite way the papal prerogative.
Cullen is the most important Irish political figure in the thirty years between Daniel O’Connell and Charles Stewart Parnell. In political matters Cullen makes it a rule to support every measure, whatever its provenance, conducive to the interests of his vision for the Roman Catholic Church in Ireland. Cullen is also a frequent visitor at the vice-regal lodge to lobby the government.