Ingram, Thomas Dunbar (1826–1901), barrister and historian, was born 28 July 1826 in Newry, Co. Down, second son of the Rev. William Ingram and Elizabeth Ingram (née Cooke). His elder brother was the economist, poet, and academic John Kells Ingram (qv). Receiving a primary education in Newry, he matriculated at QCB (1849) and graduated BA and LLB (1853). Entering Lincoln's Inn, London (24 January 1854), he was called to the bar (17 November 1856), simultaneously pursuing legal studies at London University, where he graduated LLB (1857). After several years in practice he prepared a study of the law of compensation, which went through two editions in the 1860s. As a result he was called to take up the post of professor of jurisprudence in Hindu and Islamic law in Presidency College, Calcutta (1866). Occupying the post there until 1877, he also practised in the high court of judicature. His occasional writings turned on questions of government and society in the sub-continent.
Returning to Dublin in 1877, he applied himself to Irish history, producing between 1887 and his death three heavily polemical works on issues of political contention in Anglo–Irish relations: A history of the legislative union of Great Britain and Ireland (1887); Two chapters of Irish history (1888); and A critical examination of Irish history (2 vols, 1900). His main theme was a counter-argument to the popular home rule view that the act of union had been engineered by systematic corruption on the part of the British executive. In effect, much of his labour amounted to a fierce critique of the work of the historian W. E. H. Lecky (qv), whom he reproved for ‘infinite folly, prejudice and ignorance’ (quoted in McCartney, 149), factual error, partiality, and misrepresentation. Ingram's own work was less the product of original research than a passionate pro-unionist commentary on previous research. However in fairness to Ingram, it seems that Jasper Joly (qv) refused to allow him to survey what later became the Joly pamphlet collection in the NLI, owing to violent political differences. Ingram died 30 December 1901 in Dublin and was buried in Mount Jerome cemetery. He never married.