Barbour, Sir John Milne (1868–1951), industrialist and politician, was born 4 January 1868 at The Fort, Dunmurry, near Lisburn, Co. Antrim, son of John Doherty Barbour (chairman of one of Ulster's biggest flax-spinning firms) and Elizabeth Law Milne Barbour of Edinburgh. He was educated at Harrow, Oxford (BA 1888), and at Darmstadt, Germany; entered the family business; and in 1904 succeeded his father as chairman and managing director of the Linen Thread Co., then the largest thread-manufacturing combine in the world. He held the chair till 1947; the company survived the general decline of the linen industry and the transition to man-made fibres. In 1911 he became chairman of the Belfast chamber of commerce, and gave evidence to the Primrose committee on Irish finance.
He sat in the NI parliament as unionist MP for Antrim (1921–9) and Antrim South (1929–51), and was parliamentary and financial secretary to the NI finance ministry from 1921, serving also as minister of commerce from 1925. In 1941 he became minister of finance under the premiership of J. M. Andrews (qv), having declined the position, on the grounds of his age and business interests, when it was offered by James Craiq (qv) in 1937. Barbour was politically more broad-minded than most of his colleagues, and favoured proportional representation and the wider employment of catholics in the NI civil service; however, he was economically conservative, disliked spending on social services, made little effort to attract industry, and became identified with the chronic unemployment of the inter-war years and with failure to mobilise the economy in wartime. By the time of Craig's death, Barbour already appeared to some as a liability to the government; his continuing in office was one focus of the discontent among unionists that led to the replacement of Andrews by Sir Basil Brooke (qv) and the formation of a new ministry. He was made a baronet on leaving office in 1943, and continued as an MP till his death; he was never opposed in any election for Antrim South.
He married (1899) Eliza Barbour (d. 1910) of Paterson, New Jersey, USA; they had one son (killed in an air crash, 1937) and three daughters. It has been suggested that ‘his accumulation of . . . offices verged on the obsessive’ (Johnson) because of his wife's death; they included (as well as his roles in politics and manufacture) directorships in several companies; membership of the Belfast harbour commission, the general synod of the Church of Ireland, the senate of QUB, clubs, sporting organisations, and the masonic order; and presidency of the Royal Ulster Agricultural Society, the Royal Victoria Hospital, and the NI Scout Council. He died 3 October 1951 at Dunmurry.