Brady, William Maziere (1825–94), clergyman and historian, was born 8 January 1825 in Dublin, son of Sir Nicholas William Brady (1791–1843), manufacturer of gold and silver lace, of Willow Park and Killiney Park, Co. Dublin, and Catherine Anne Brady (d. 1839), daughter of Peter Jacob Hodgson, comptroller of the customs, Dublin. Sir Nicholas (knighted by George IV when he visited Dublin in 1821) was lord mayor of Dublin 1839–40. Entering TCD as a pensioner 4 July 1842, William graduated BA (1848), MA (1853), BD (1858), and DD (1863). In 1848 he was ordained deacon at St Patrick's cathedral, Dublin, and a priest at Lisburn; he held curacies at Maynooth (1848), Kilkeedy, Co. Limerick (1849), and St Dolough's, Dublin (1851). He became rector of Farrahy (1851), vicar of Clonfert (1861), and rector of Kilberry, Co. Meath, and served as chaplain to the viceroys Clarendon (qv), St Germans (qv), and Carlisle (qv) until he made a speech criticising the established church, which led to his omission from the viceregal list in 1864.
A noted ecclesiastical historian, he was a meticulous scholar and industrious researcher. He edited the impressively detailed Parish records of Cork, Cloyne and Ross (3 vols, London, 1866). During the 1860s he engaged in thorough research on the transition from the Marian to the Elizabethan episcopate and went to Rome, where he became acquainted with Patrick Francis Moran (qv), vice-rector of the Irish College, a convinced ultramontanist and later cardinal archbishop of Sydney, who assisted him in his research. Brady concluded that no Irish-born catholic bishops had converted to protestantism and thus the claim of the Church of Ireland that it was the ‘true catholic church’ with an unbroken episcopal succession was false. He published his findings as The alleged conversion of the Irish bishops to the reformed religion, at the accession of Queen Elizabeth; and the assumed descent of the present established hierarchy in Ireland from the ancient Irish church, disproved (London, 1866). He had prefaced his work by saying that he had no intention of undermining the status of the established church, and that he was simply opposed to historical misrepresentation. However, with disestablishment in the offing, the work caused a sensation: it went through five editions in two years and attracted rebuttals from many protestant scholars including E. A. Stopford (qv), William Lee (qv), W. H. Hardinge (1800–70), and J. A. Froude (qv). To bolster his argument he also published State papers concerning the Irish church in the time of Queen Elizabeth (London, 1868).
He contributed numerous letters and articles in favour of church disestablishment to contemporary publications, many of which appeared in his Essays on the English state church in Ireland (London, 1869). In Some remarks on the Irish church bill (London, 1869), he argued that it was ‘shameful and wicked’ that a privileged minority, in order to avoid supporting its own clergy, should be ‘willing to jeopardise the English church establishment, to delay the pacification of Ireland, to imperil the union between the two countries and to embroil the two branches of the imperial legislature in a dangerous constitutional quarrel’ (p. 4).
His arguments had moved him closer to Rome, and after a further period of research in the Vatican archives he resigned his anglican positions and converted to Roman Catholicism in May 1873. This research was published as The episcopal succession in England, Scotland and Ireland, A.D. 1400 to 1875 (Rome, 1876–7) and Annals of the catholic hierarchy in England and Scotland, 1585–1876 (London, 1883). He moved to Rome, where he acted as correspondent for the London Tablet. A unionist in politics, he corresponded with Gladstone, and published a pamphlet, Rome and Fenianism: the pope's anti-Parnellite circular (London, 1883), supporting papal criticisms of the Parnellites. In 1890 he published the Anglo–Roman papers (Rome), a miscellaneous collection of historical material relating to England based on research in the Roman archives, in which he condemned the assistance given by successive British governments to the unification of Italy and the dissolution of the papal states. He was appointed cavalier of the order of Pius IX and private chamberlain to Pius IX and Leo XIII. He died 19 March 1894 in Rome and was buried there.
He married (1851) Frances O'Reilly of High Park, Dublin. His uncle Sir Maziere Brady (qv) was three times lord chancellor of Ireland, and another uncle, Francis Tempest Brady (1808–71), was rector of St Mary's, Clonmel, and chancellor of Lismore (1861–71).