Henderson, James (1797–1863), newspaper proprietor, was one of possibly five sons of James Henderson, a prominent merchant in Belfast, and Amelia Henderson (née Magill or McGill), both of Castlereagh, Co. Down; there were also two daughters. One of his brothers, Alexander Henderson (1805?–1868), was intended for a career in business, but after a serious illness studied for the presbyterian ministry, was librarian (1823–9) of the Linen Hall Library, Belfast, then presbyterian minister of Lisburn, Co. Antrim, and finally became the first presbyterian chaplain in the British army. Henry Henderson (1820–79), another brother, was a presbyterian minister in Holywood, Co. Down, who wrote much on religion and politics for one of the family's newspapers, the Belfast Weekly News, over the pen-name ‘Ulster Scot’, and who also wrote seven novels, including The true heir of Ballymore: passages from the history of a Belfast Ribbon lodge (1859), in all of which a thin coating of fiction strained to cover polemic.
James Henderson of Newry, one of the older children of James Henderson of Castlereagh and Belfast, had six daughters and five sons with his two wives, Annie Peacock (d. 1844), and Eliza Jane Magill (née Knox), who survived him. Before becoming proprietor of the Newry Telegraph in 1823, James had worked for Alexander Mackay, who had come from Edinburgh to take over the Belfast News Letter from the family of Francis Joy (qv). When Mackay died (1844) his son's widow asked Henderson's advice on what to do with the newspaper that she and her three daughters had inherited; he sent his son James Alexander Henderson (1823–83), aged 21, to be the editor from April 1845. On 11 December 1845, in Fisherwick Place church, Belfast, J. A. Henderson married one of the three girls, Agnes Mackay, and they eventually became sole owners of the paper. The young man continually improved the paper: he bought new type in 1846 and increased the paper's size and frequency of publication; in 1852 he published the first pictures in an Ulster newspaper, woodcuts of the funeral of the duke of Wellington (qv). It became a daily paper in 1855, and in 1861 was Ulster's first penny daily. In 1858 the Belfast News Letter was the first in Ulster to have its own London correspondent. It moved several times to larger premises, and in 1874 to impressive new buildings; new machinery was installed again in 1880. James Alexander Henderson was president of the Newspaper Society in 1862 and one of the founders of the Press Association in 1868; he was mayor of Belfast in 1873–4. He died in April 1883.
His eldest son James Henderson (1848–1914), later Sir James, was born in Mount Collyer Park, Belfast, on 26 April 1848, and attended Rev. George Wilson's private school; he graduated BA from TCD, kept terms at King's Inns as well as the Middle Temple, and was called to the Irish bar in 1872 by his father's friend from Newry, Lord O'Hagan (qv). He went on circuit for a short time till at his father's urgent request he took on the position of editor of the Newry Telegraph, which rapidly returned to profitability. On his father's sudden death in 1883, James Henderson took over the two Belfast papers (the News Letter and Belfast Weekly News), and with great energy and enthusiasm introduced new technology and procedures: linotype machines and the first direct telegraph link to London were rapidly set in place, and he was ahead of his competitors in publishing special supplements in the paper. Alongside his business interests, Henderson devoted much attention to civic and public life: he was a borough councillor of Belfast for twenty-six years, and alderman from 1894. He was the city's first lord mayor (1898) and the first high sheriff of the new county of the city of Belfast (1900); he took a great interest in technical education, and was credited with establishing the acclaimed Municipal Technical Institution, as well as the new Belfast museum, which opened after his death. He donated 3,000 reference works to the town's new library, which opened in 1888. He was made a freeman of the city of Belfast (1912), was a member of the senate of QCB from 1900, and president of the Federation of Master Printers in 1904. He was knighted in 1899; his wife Martha Ann, daughter of David Pollock of Newry, set up several pioneering day nurseries for poor children in Belfast during her time as lady mayoress. Sir James and his wife had five sons and one daughter; one son died young. Sir James died of heart failure on 1 May 1914.
One son was killed in action in 1917; the eldest surviving son, James Henderson (1889–1963), was a barrister who served throughout the first world war in the Army Service Corps and returned to work in the family business, first in the editorial department and from 1928 as a manager and director. He was president of the Newspaper Society (1936–7), chairman of the Press Association (1940, 1945), a director of Reuters (1936–41), president of the Golfing Union of Ireland (1946, 1947), and a member of the senate of QUB. He married Primrose Ewart, closely related to the scholar and Christian apologist C. S. Lewis (qv), and died 30 July 1963.
Sir James Henderson's third son, Oscar Henderson (1891–1969), born 7 October 1891, was a RN commander who served with distinction in the Gallipoli campaign and the Zeebrugge raid (1918), and from 1922, after he left the navy, was private secretary to the first governor of Northern Ireland, the 3rd duke of Abercorn (qv); he thus played a central role in the establishment of the new structures of NI after partition. On his retirement (1947), he became a managing director of the family business, and from 1963 was president of the firm, renamed Century Newspapers. Oscar Henderson was one of the first directors of the commercial television company Ulster Television, of which he had been the major promoter from the late 1950s. He was awarded the DSO, Croix de Guerre, CBE, and CVO. He married (1920) Alicia Mary (‘Molly’), daughter of R. B. Henry of Belfast, and died 3 August 1969, survived by two sons. One son, R. B. Henderson, was managing director of Ulster Television, and the other, Capt. (Oscar) William James Henderson, was Stormont MP for Belfast (Victoria) 1953–8, and chairman of Century Newspapers when it was bought by the Thomson newspaper group in 1989.
Other family members were involved with printing and journalism throughout the nineteenth and twentieth centuries. Starting with Alexander Mackay in 1795, one family continuously owned the Belfast News Letter for 194 years, an association unique in newspaper history. The family's presbyterian and unionist outlook set the tone for their paper, which for five generations exerted an unparalleled influence on public opinion in the north of Ireland.