Archbishop of Armagh; b. Dublin, 1606; d. Saumur, France, March 1669. O'Reilly was educated and ordained (1629) in Dublin, where he also did parish work. In 1633 he went to the Louvain, where he studied under the Jesuits and Franciscans before his appointment as prefect of Irish secular priests and seminarians resident at the Louvain. O'Reilly returned to Ireland in 1641. He supported the Irish rebellion, serving as governor of Wicklow (1642). Archbishop Thomas Fleming of Dublin appointed him vicar-general and apostolic administrator (1642–48) while Fleming was at Kilkenny, seat of the Catholic Confederation. O'Reilly's sympathies were with the independence faction of the rebels, and he opposed any truce with the royalist James Butler, Marquis of Ormond, who sought Irish aid against the English parliamentary forces. Fleming replaced O'Reilly as vicargeneral in 1649 but restored him in 1650. In 1653 O'Reilly was arrested, imprisoned, and charged with a murder that had occurred while he was governor of Wicklow. He was tried (Sept. 6–7, 1654), found guilty, and pardoned; finally, he left Ireland. O'Reilly fled to Lille, where he received his appointment as archbishop of Armagh, although he did not receive the pallium until 1657. He attempted to return to Ireland by way of London, but fearing possible arrest in England, O'Reilly returned to France. It was not until 1659 that he reached Ireland, where he remained until the Stuart restoration (1661). The Spanish ambassador in London accused O'Reilly of anti-Stuart activities, and for this Pope Alexander VII recalled the primate to Rome (1661–65), where he appears to have vindicated himself. In 1665 O'Reilly visited Ireland and attended the national synod held in Dublin (1666). His opposition to the pro-English activities and remonstrance of Father Peter walsh angered Ormond, who imprisoned the primate for three months. O'Reilly, exiled once again, went to France, where he died.
Bibliography: a. f. pollard, The Dictionary of National Biography from the Earliest Times to 1900, 14:1140–41. r. bellings, History of the Irish Confederation and the War in Ireland. 1641–1649, ed. j. t. gilbert, 7 v. (Dublin 1882–91). e. curtis, A History of Ireland (6th ed. New York 1951). r. bagwell Ireland under the Stuarts, 3 v. (London 1909–16).
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