O'Connell, Count Daniel Charles (1745–1833), French general and count in the French nobility, was born 21 May 1745 in Derrynane, Co. Kerry, twenty-first among twenty-two children (of whom thirteen survived childhood) of Donal Mor O'Connell (1701–70), catholic landowner, and his wife Mary (c.1708–1795), daughter of Daniel O'Donoghue of Glenflesk, Killarney. Daniel was tutored at home in Latin and Greek, and before he was 16 left with his cousin, Murty O'Connell, to join the French army. On 13 February 1760 he became a cadet in the infantry regiment of the Royal Suédois. He was to spend almost his entire career in France or serving abroad with French regiments, but remained in close contact with his family, being in constant correspondence with the head of the clan, his brother Maurice O'Connell (qv), ‘Hunting Cap’, who was almost twenty years his senior, and later arranging army appointments for a host of young nephews and cousins.
O'Connell served with the Royal Suédois in the last two campaigns of the Seven Years War and was made assistant adjutant (sous-aide-major) of the regiment. At the close of the war, he was recommended for the military academy of Strasbourg (1765–6). He had a talent for self-advancement and was well regarded by his seniors, being tall, strong, handsome, disciplined, industrious, and sober. He had an almost morbid horror of drink, and his great boast was that he had never wasted a moment of his time or a farthing of his money. Appointed to Col. Meade's regiment of Clare's Irish brigade with the rank of captain (October 1769), he set sail immediately for Mauritius. Two years later he was allowed a visit home to Kerry for the first time in eleven years. In 1775 the death of Clare's son and the extinction of the title resulted in the reduction of the Irish brigade, and destroyed O'Connell's chance of promotion. He devoted himself to the study of chemistry, literature, and the military. A published study, ‘Discipline of the army’, came under the notice of the military authorities, who obtained for him a cross of St Louis, a pension of 2,000 livres a year, and the rank of lieutenant-colonel with which he was posted to his old regiment, the Royal Suédois (1778). With them he served at the taking of Minorca (1781) and was severely wounded at the siege of Gibraltar (1782) but managed to save the life of the duc d'Artois, the future Charles X. For these services he was made a count, one of only twenty-two people outside the royal family to receive this honour, and was made colonel of the German regiment of Salm-Salm in French pay, which at a grand review of 30,000 French troops in Alsace (1785) was pronounced the best regiment. He began to move in court circles and in 1788 kissed the hand of Marie Antoinette and rode in the king's coach.
In 1788 he recommended to Hunting Cap the college of Saint-Omer as a suitable school for his nephews, Maurice and Daniel O'Connell (qv), but – taking belated notice of the gathering revolutionary storm – tried unsuccessfully to dissuade them. In the crisis of summer 1789 he allegedly announced his readiness to move his regiment into the capital to disperse revolutionary mobs, but could not obtain the king's permission. In 1790 his men mutinied, leaving him in the anomalous position of a colonel without a regiment. A protégé of the ancien régime, O'Connell nevertheless remained in Paris in 1790–91, serving the nouveau régime as a member of a commission engaged in revising army regulations. However, in 1792 he joined the duke of Brunswick's émigré army at Koblenz and took part in the disastrous battle of Valmy in Berchini's regiment. Ever cautious, he served as a private, refusing any command so that his name should not be mentioned in France. In November 1792 he was in London, almost penniless and bent on concealing that he had served against the republic. An alibi was procured and attested at Tralee to the effect that O'Connell had been in Ireland all the time, and was forwarded to Paris to prevent the confiscation of property. In London O'Connell petitioned Pitt to reconstruct the Irish brigade in the service of George III. Six regiments were raised, with O'Connell appointed colonel of the 4th, but the scheme was only partially realised: three of the regiments were sent to the West Indies and Nova Scotia, where they succumbed to pestilence. By 1798 the brigade had entirely ceased to exist, though O'Connell retained his full pay as a British colonel, which he drew to the end of his life. At this period his name was mooted by Gen. Henry Clarke and Wolfe Tone (qv) as a possible commander of their troops. Clarke gave his opinion that O'Connell was a good parade officer but had no genius in command, to which Tone replied that he ‘was in favour of his being employed for I know he hates England’ (Tone, Autobiography, 302).
O'Connell married (1796), at the French chapel in Covent Garden, Martha, comtesse de Bellevue (née Drouillard de Lamarre; d. 1807), a young widow with three children. In 1802 he took advantage of the peace of Amiens to return to France. On the renewal of war the couple were detained by Napoleon as British subjects, and remained virtual prisoners in France till the restoration of the Bourbons (1814). Back in favour, O'Connell received the rank of lieutenant-general in the French army and commander of the order of St Louis. His fortunes revived, he advanced a large sum to his nephew Daniel to save him from bankruptcy in 1815 and came to his rescue again in 1818, though by this date he had already settled the bulk of his fortune on his great-nephews. The count followed his namesake's career with keen interest, but his advice was invariably cautious and was not much heeded; he counselled loyalty and submission to the crown, and while he supported emancipation he deplored repeal. After the revolution of 1830 O'Connell refused to take the oath of allegiance to Louis Philippe and was struck off the military list, though he became a naturalised French citizen in 1831. He died on 9 July 1833 at the Château Bellevue at Madon, near Blois, and was buried at the cemetery at Coudé. He had no children and his title, though not his fortune, descended to his godson, the baron d'Eschegoyen's second son, who took the name O'Connell. A portrait by Paul Guérin hangs in Derrynane House.