Blackwell, James Bartholomew (c.1765–1820), soldier, was born in Ennis, Co. Clare. Aged about ten, he was sent to Paris to be educated for the priesthood at the Irish College, where his maternal granduncle, Dr Bartholomew Murray, MD, had established a bursary. However, he switched to studying medicine at the Hôpital la Bicêtre and qualified as a surgeon. A tall, handsome man, eager for adventure, he joined the French army's Esterhazy Hussars, becoming a naturalised French subject in 1784. Before the revolution he associated with the Orleans group of reformers. He claimed to have led the militant Faubourg St Antoine in the attack on the Bastille (14 July 1789), but his name does not appear on the official list of vainqueurs de la Bastille. Veracity was probably not one of his virtues: when he was imprisoned in Kilmainham (1799–1801) the prison chaplain noted that ‘he cannot for a moment adhere to truth’ (Reb. papers, 620/49/70). When foreign regiments were disbanded in 1791, he was promoted to captain of the hussards braconniers (21st Cavalry Regiment) and in 1793 served under Dumouriez. During the Terror in 1794 Blackwell intervened at a revolutionary tribunal to save the lives of an English soldier, Col. Wade of Somerset, and his daughter Sophie, whom he married soon afterwards. Blackwell later fought a duel with his lieutenant, the famous Joachim Murat, believing him to have paid excessive attention to his wife. However, this resulted in no lasting ill-will between them, and he claimed that he and Murat distinguished themselves in preventing royalists from seizing artillery in the attempted coup of October 1795.
Blackwell sailed on Hoche's expedition to Bantry Bay in December 1796, and in 1797 he befriended and supported Fr James Coigly (qv), then penniless in Paris. He gravitated towards the James Napper Tandy (qv) faction of Irish émigrés in Paris, and acted as Tandy's adjutant-general in the small expedition that sailed on the Anacréon from Dunkirk and landed at Rutland Island, Co. Donegal, on 16 September 1798. Blackwell later claimed that since Tandy was such a poor leader and was ‘always drunk and incapable of acting’ (Coughlan, 136), it fell to him to direct the expedition; a government informant noted that Blackwell had Tandy ‘like a child in leading strings’ (Castlereagh corr., i, 406). On learning of Humbert’s (qv) defeat they reembarked for France, but their ship was damaged in a fight at sea and they had to sail for repairs to Bergen, Norway. In the guise of American merchants they travelled overland to the free city of Hamburg, arriving on 22 November 1798. Waiting for passports from the French consulate, they met their comrades Hervey Montmorency Morres (qv) and William Corbet (qv) and dined at the house of Pamela Fitzgerald (qv). Also present was the spy Samuel Turner (qv), who notified the British consul, Sir James Crauford, that they intended to leave the next morning. Crauford prevailed on the Hamburg authorities to arrest them and at 5 a.m. on 24 November 1798 Tandy, Blackwell, Morres, and Corbet were taken from their hotel and imprisoned in chains in police dungeons. Blackwell attempted to assert his rights as a French officer, sending a stream of letters to the French authorities in which he complained bitterly of his appalling prison conditions, and detailed his loyalty and services to France. The letters were intercepted by the Hamburg police, but eventually he managed to contact the French government by writing a note in blood and throwing it into the street, and his conditions improved in late 1798. The prisoners proved a serious embarrassment for Hamburg: France demanded their release; Britain demanded their extradition; and Russia, Britain's ally, threatened to invade Hamburg unless they were handed over to Britain. On 30 September 1799 the four prisoners were extradited to England, and a furious diplomatic storm erupted: France broke off diplomatic and trade relations with Hamburg, and the issue was raised with Britain by Prussia, Holland, and even her ally Austria. As they were brought to Newgate prison in London, huge crowds gathered to see the men who had become such a cause célèbre throughout Europe. Held briefly in Newgate (31 October–9 November), they were transferred to Kilmainham prison, Dublin, where Blackwell quarrelled with his colleagues, especially Tandy, and refused to dine with them. He also regularly complained about the food, claiming that his health was so poor that he could only eat oysters, with which he was liberally supplied. His health undoubtedly suffered in prison, and he had what appears to have been an epileptic fit and became extremely depressed. He and his wife regularly petitioned for his release on the grounds that he was a French soldier who had simply obeyed his government's orders, and Bonaparte also protested at his continued detention. He was released from Kilmainham 10 December 1801, after Britain and France signed peace preliminaries.
Soon after his return to France he was appointed chef-de-bataillon of the newly-formed Irish Legion. In the faction-torn legion he sided with the Arthur O'Connor (qv) party and supported Thomas (qv) and William Corbet (qv) in their dispute with John Swiney (qv). An inquiry into this dispute strongly criticised his intrigues and his weakness as commander, and recommended his removal to another unit. In 1805 he joined a cavalry regiment of the Grand Army and fought in the Prussian and Austrian campaigns; he may also have served in Russia. Wounded several times, he retired on half pay as a colonel and was appointed governor of the town of Bitche, northern France (September 1813). He served under the Bourbons, being made governor of the town of La Petite Pierre in August 1816 and brevet-officer of the Royal Order of the Légion d'honneur in July 1819. He died in Paris in 1820 and was buried in Père Lachaise cemetery. A collection of his papers is held in the NLI.