Barton, Sir Dunbar Plunket (1853–1937), lawyer, politician, judge, and author, was born 29 October 1853 in Merrion Square, Dublin, eldest child of Thomas Henry Barton (d. 1878), BL, DMP magistrate (a descendant of the founder of the Barton and Guestier Bordeaux wine merchants), and the Hon. Charlotte Plunket (d. 1918), third daughter of the 3rd Baron Plunket. He was a nephew of the Church of Ireland archbishop of Dublin, William Conygham Plunket (qv), 4th Baron Plunket, and was proud of his descent from Charles Kendal Bushe (qv). The family later lived at 22 Longford Terrace, Monkstown, Co. Dublin. Barton liked to recall that as a boy his father asked him to estimate the distance between his mother's bedroom window and the corresponding room in the next house, then told him always to remember that had he been born fifteen feet further east he would have been a Roman catholic, and to be tolerant.
Educated at Harrow (1867–73) and Corpus Christi College Oxford (matriculated 1873), Barton was elected president of the Oxford Union in 1877 but did not formally graduate BA till 1893. Although admitted to the Inner Temple in 1875 he was not called to the Irish bar until 1880 (English bar 1893). While studying at King's Inns, Barton frequently attended the Trinity College Literary and Historical Society and participated in its debates (as an Oxford Union member he was entitled to do this). He continued to attend the society regularly in later years. (When the Dublin University Law Society was founded Barton became its first vice-president and established an annual medal for the best composition on a legal subject selected by the president of the Society; he later succeeded Gerald Fitzgibbon (qv) as president.)
In 1880 Barton was briefly private secretary to the lord lieutenant of Ireland, the 7th duke of Marlborough (qv). During the 1880s and early 1890s he combined his legal practice with speechmaking and electoral work for the conservative party and pro-landlord groups. In 1885 he became private secretary to the lord chancellor of Ireland, Lord Ashbourne (qv). He lectured at the King's Inns (1885–91); the future Serjeant A. M. Sullivan (qv), who studied under him, remarked that while such lectures were usually dull, Barton made them interesting. Barton showed the conciliatory side to his character when he sided with the other King's Inns lecturer, J. G. Swift MacNeill (qv) when the benchers sought to dismiss him on the grounds that MacNeill's parliamentary activities as a nationalist MP were incompatible with his teaching duties. Not noted for his eloquence in court, Barton took silk in 1889, undoubtedly assisted by his uncle, David Plunket (qv), later Lord Rathmore. Barton was elected a bencher of the King's Inns in 1891.
In 1893 Barton became unionist/conservative MP for the strongly farming constituency of Armagh Mid, retaining the seat at the 1895 general election and an 1898 by-election. He developed a reputation as a fluent speaker and was widely liked. In the debate on the second home rule bill Barton told the house of commons (Hansard, 4th ser., x (1893), 1705) that he had enrolled himself in an organisation pledged to resistance if the bill was passed and might spend some considerable time in penal servitude as a result. Michael Davitt (qv) retorted that Barton would probably end up as an Irish judge – a standard jibe at the professional ambitions of Irish unionist lawyer-politicians – and that ‘he will never reach the bench by way of the dock’ (MacNeill, 307).
Appointed solicitor general for Ireland (1898–1900), Barton was elected a bencher of Gray's Inn in 1899. A director of Messrs Arthur Guinness & Son & Co. Ltd (1891–1900) he served as a judge of the high court of justice, Ireland, queen's bench division (1900–04). Between 1904 and his retirement in January 1918 he held the office of chancery judge. Barton was initially seen as a lightweight political appointment. Early in his judicial career a number of his decisions were referred to the Irish court of appeal, but with experience he garnered respect for his judgment so much so that the house of lords, in the case of Black v. the Scottish Temperance Association Co., preferred his opinion to that of the court of appeal. He was known as a courteous judge who disliked rough exchanges between lawyers in his court, and despite his political antecedents he came to be regarded as the most fair-minded judge on the Irish bench. His publications on legal matters included a commentary on the 1896 land act and two important sections of Lord Halsbury's The laws of England (1908) – those on partnership and perpetuities.
Barton developed a close friendship with T. M. Healy (qv) from the time of Healy's election as a bencher of Gray's Inn in 1910; they joined in advising the numerous Irish students who attended that establishment, and in 1933 Barton published T. M. Healy: memoirs and anecdotes. (H. E. Duke (qv) was also a bencher of Gray's Inn, and the association contributed to Healy's close cooperation with Duke during his Irish chief secretaryship.) Maurice Healy jr (qv) and A. M. Sullivan also regarded Barton as a close personal friend despite political differences. Barton was regarded as the preeminent authority on the history and associations of Gray's Inn; he was a regular contributor to its journal Graya, and in 1924 published The story of our Inns of Court.
Barton greatly admired the Napoleonic marshal and king of Sweden, Jean-Baptiste Bernadotte, whom he saw as chivalrous and a lover of order. Barton acquired numerous Bernadotte documents and memorabilia, and devoted considerable time and effort to a multi-volume biography – Bernadotte: the first phase (1914), Bernadotte and Napoleon (1920), and Bernadotte, prince and king 1810–44 (1925). The amazing career of Bernadotte 1763–1844 (1929) is a one-volume summary.
Barton was MRIA (1917) and received an hon. D.Litt. (1926) from the NUI. He was also a fellow of the Royal Historical Society, the Irish College of St Columba, and the RSAI. A member of the Dublin branch of the British Empire Shakespeare Society, he was also the author of Links between Ireland and Shakespeare (1919) – an anecdotal work relying heavily on associations, speculation, gossip amongst the Irish antiquarian community, and Arnoldesque comments about Celtic racial characteristics – and Links between Shakespeare and the law (1929). Conferred with a baronetcy in 1918 and sworn of the Irish privy council in 1919, he was appointed treasurer and resident bencher of Gray's Inn in 1922.
Barton's career illustrates the abiding importance of clubability in Irish political and professional life. He was a member of the Kildare Street, Sackville Street, and University Clubs (Dublin) and the Athenaeum, Carlton, Garrick, St James's, Beefsteak, and Constitutional Clubs (London). An enthusiastic yachtsman, he was a member of the Royal St George and Royal Irish Yacht Clubs, which may have influenced his appointment as a commissioner of Irish lights (1918–22). He was a senator of the NUI (1909), a member of the Irish War Aims Committee (1919), chairman of the executive committee of the Irish National War Memorial, trustee of the NLI (from 1920), chairman of the industrial court under the Industrial Courts Act, 1920, and a member of the royal commission on Defence of the Realm Losses, 1920 (later called the War Compensation Court). Barton was also president of the Royal Victoria Eye and Ear Hospital (Dublin), a governor of the Royal City of Dublin Hospital, and the first vice-president of the Irish Genealogical Research Society.
Barton was also an enthusiastic golfer, president of the Golfing Union of Ireland (1906–26) and of the Royal Portrush, Royal Dublin, and Greenore golf clubs, and holder of honorary positions with many other Irish clubs. He presented the Barton Shield for foursomes competitions (originally an inter-county contest, it flourished after being changed to inter-club), a cup to the Press Golfing Society, and the Barton Cup, played for by clubs in Leinster. He encouraged the golfer Pam Barton (who won both the British and US women's titles in one year) after discovering that she was his second cousin once removed. According to Maurice Healy jr, Barton played a greater role than any other man in popularising golf in Ireland (Old Munster circuit, 41). He died 11 September 1937 at his residence, 2 Gray's Inn Square, London. The Irish Times death notice read ‘No flowers and no mourning by request’.
He married (5 October 1900) Mary Tottenham (d. 1928) of Dublin. In Dublin the family resided on Clyde Road. They had one son, Dunbar Patrick (d. 1929).