Alexander, William (1824–1911), Church of Ireland bishop of Derry and Raphoe, and archbishop of Armagh, was born 13 April 1824 in Derry city, eldest of three sons and third child among eight children of Robert Alexander, rector of Termoneeny and subsequently prebendary of Aghadowey, Co. Londonderry, and his wife Dorothea, who inherited family property in Rathdonnell, Co. Donegal, from her father, Henry McClintock. One brother, Henry (d. 1896), became a rear-admiral; another, Robert Alexander, was – like another Ulster soldier, John Nicholson (qv) – killed in action at the siege of Delhi (1857); a sister married the dean of Derry. William was great-nephew to Nathaniel Alexander (d. 1840), bishop of Meath, and a great-grandnephew of James Alexander (qv), 1st earl of Caledon. He was educated at Tonbridge School in Kent, and won an exhibition to Exeter College Oxford in 1841. However, his university career was unimpressive, and after six years he left Oxford with large debts and with a fourth-class degree. He was deeply affected by the Oxford movement, and in 1845 almost became a Roman Catholic; a quaker lady, whom he met on his journey home to tell his parents of his conversion, dissuaded him. He returned to Oxford, and as a member of Brasenose College graduated BA in 1854; his recitation of an ode he had written at the installation of the chancellor of Oxford University in June 1853 made a considerable impression. Ordained priest on 18 June 1848, he was a curate in St Columb's cathedral, then held the benefices of Termonamongan, Fahan, and Camus-juxta-Mourne in Derry diocese, and was dean of Emly (a sinecure) 1864–7. On 6 October 1867 he was consecrated bishop of Derry and Raphoe; he was subsequently chaplain to three lords lieutenant of Ireland, and was elected archbishop of Armagh on 25 February 1896.
An accomplished preacher and poet (as was his wife), he had been a candidate for the chair of poetry at Oxford in 1867, and published two books of poetry (1867, 1886). Alexander was celebrated in Britain, Ireland and America for his discourses and sermons, and esteemed by lay people and clergy. In June 1869 he made a notable attack in the house of lords on the proposed disestablishment of the Irish church, and his opposition to home rule was evident in an impressive speech in the Royal Albert Hall, London, in 1893. His publications were mainly on theological subjects; he received an honorary LLD from TCD (1892) and the degrees of hon. DCL (1876) and hon. D.Litt. (1907) from Oxford. He resigned his see on 1 February 1911, and died in Torquay, 11 September 1911. He was buried beside Derry cathedral.
He married (15 October 1850) Cecil Frances Humphreys (Cecil Frances Alexander (qv)). They had two sons and two daughters, one of whom, Eleanor Jane Alexander (qv), edited her father's autobiographical writings and added a memoir.