Dictionary of National Biography, 1885-1900/O'Sullivan, John
O'SULLIVAN (Sir) JOHN (fl. 1747), colonel in the French service, came of the O'Sullivans of Munster, and was born in co. Kerry about 1700. The family being catholics, their estates were in the hands of protestant trustees. At the age of nine O'Sullivan was sent abroad to be educated for the catholic priesthood. He spent six years in Paris, and then went to Rome. On the sudden death of his father, O'Sullivan returned to Ireland; but, disliking the conditions under which Irish catholics were compelled to live by the penal laws, he sold his interest in the family property and emigrated to France. He obtained the post of tutor to the son of Marshal Maillebois. On Maillebois's recommendation he then entered the French army. In 1739 he attended Maillebois as secretary in an expedition to Corsica. During the first four years of the Austrian succession war he took part in the French campaigns in Italy and on the Rhine. In 1745 he was appointed adjutant-general to the young pretender, then preparing for the invasion of England. He landed with him at Lochnanuagh on 5 Aug. 1745, and through the whole campaign he remained his chief adviser in both civil and military matters. O'Sullivan commanded with Cameron of Lochiel the nine hundred highlanders who captured Edinburgh on 16 Sept. 1745 (Lockhart, Memoirs, ii. 488). He was present at Prestonpans, and, in his capacity as adjutant and quartermaster-general, drew up the rebel army in line of battle at Culloden. O'Sullivan escaped back to France on 1 Oct. 1746. In 1747 he was knighted by the pretender for his services. The date of his death is unknown. He married a Miss FitzGerald, and left a son.
Thomas Herbert O'Sullivan (d. 1824), son of the above, who entered the Irish brigade, was appointed to accompany the privateer Paul Jones in his expedition against the Irish coast in 1779. O'Sullivan quarrelled with his fellow-commander and fled to America, where he entered the British army under Sir Henry Clinton at New York. He left the British army, probably at the end of the American war of independence, 1783, and entered the service of Holland. He died a major in the Dutch service at the Hague in 1824. His son, John O'Sullivan, employed in the American consular service, died in 1825.
[O'Callaghan's Irish Brigades; Webb's Compendium of Irish Biography.]