Plunket, Benjamin John (1870–1947), bishop and estate-owner, was born 1 August 1870 at Bray, Co. Wicklow, younger son and third of six children of William Conyngham Plunket (qv), 4th Baron Plunket, archbishop of Dublin 1884–97, and his wife, Anne Lee (1839–89), only daughter of Sir Benjamin Lee Guinness (1798–1868) and sister of Lord Ardilaun (qv) and of the 1st earl of Iveagh (qv). Educated at Harrow and Corpus Christi College, Cambridge, he was ordained by his father for the Church of Ireland ministry (1896). He was then successively curate of St Peter's, Aungier St., Dublin (1896–1902); rector of Aghade, diocese of Leighlin (1902–7); vicar of St Ann's, Dawson St., Dublin (1907–13); bishop of Tuam, Killala, and Achonry (1913–19); and bishop of Meath (1919–25). Amongst many ancillary appointments, he served as chaplain to the lord lieutenant 1904–13.
The Irish Times, when reporting his death, characterised Plunket as ‘a churchman of broad views. . . [who] was not afraid to utter his opinions’ (27 January 1947). Probably his most notable stand was in 1910 when, on the accession of George V, parliament passed an act to delete terms offensive to Roman Catholics from the royal accession declaration. The old declaration (introduced 1678) repudiated the mass, transubstantiation, and the invocation of the Virgin Mary and the saints. The modified form of the declaration was widely opposed, but Plunket was principal promoter of a petition to the house of commons in support of it, signed by over 3,000 representative Irish protestants. On another occasion, he was one of three Church of Ireland bishops who, with eighteen catholic bishops, signed a controversial anti-partition manifesto issued before the Longford by-election won by Sinn Féin (May 1917); the manifesto was a significant factor in Sinn Féin's narrow victory. Plunket was also an Irish-language enthusiast, encouraging Irish in Church of Ireland schools and hymns in Irish at church services.
In 1925, while still bishop of Meath, he was severely criticised by W.B. Yeats (qv) in his famous speech in the senate on divorce (11 June 1925). Plunket's uncompromising approach to sexual morality and the indissolubility of marriage had, as Yeats saw it, given succour to those intent upon passing legislation which the protestant minority in newly–independent Ireland would find ‘oppressive’. Aged 55, he resigned as bishop of Meath on health grounds (31 December 1925). He had just inherited the 500-acre estate of his late uncle, Lord Ardilaun, at St Anne's, Clontarf, on the north shore of Dublin Bay; Ardilaun (whose biography in the DNB was written by Plunket) had no children, and his widow died 13 December 1925. After a long recuperation abroad, Plunket moved into the Italianate mansion on the estate – described as ‘the most palatial house to be built in Ireland during the second half of the nineteenth century’ (Bence-Jones, A guide to Irish country houses). He lived there – somewhat uneasily – until 1939. Neither he nor his family were comfortable in such opulent surroundings, and maintenance of the house was an impossible burden. He made several unsuccessful attempts to sell the estate in the 1930s. Eventually, Dublin corporation acquired it by compulsory purchase and turned part of the lands into a public park, using the remainder for new housing. The mansion was destroyed by fire in 1943, though its shell was demolished only in 1968.
Another house within the estate, Sybil Hill – an elegant late-Georgian building, with twenty-two adjoining acres – was excluded from the compulsory purchase. Plunket retained it as his final residence. He died 26 January 1947 and is buried in the grounds of All Saints’ church, Raheny (formerly the St Anne's estate chapel). His second son, also Benjamin, inherited Sybil Hill and later sold it to the Vincentian congregation, who established St Paul's College there (1950).
Plunket married (1904) Dorothea Hester Butler (1873–1936), third daughter of Sir Thomas Butler, 10th baronet, of Cloughgrenan. They had two sons and two daughters. The younger daughter, Olive (1911–75), married (1933) the 8th Earl Fitzwilliam (1910–48): their marriage was not a success, she became an alcoholic, and he had a number of well-publicised affairs – the last with Kathleen, widow of William Cavendish (1917–44), marquis of Hartington, and sister of John F. Kennedy, afterwards US president. Kathleen and Fitzwilliam were killed in 1948 when the private plane in which they were travelling crashed in France.