Ogilvie, William (1740–1832), politician and tutor, was born in Scotland. Nothing is known of his parents, though he claimed to be related to a baronetical family of Ogilvies. His enemies alleged that he was from a humble background, though possibly educated at Edinburgh University, and that he was a schoolmaster in Dublin; some even said he had come to Ireland as a drummer in a Scots regiment. An alternative narrative suggests that he was born in Banff, Scotland, and matriculated (1757) in King's College, Aberdeen, apparently without subsequently graduating, and that he went in 1765 as tutor or companion of Sir James MacDonald, 8th baronet, of Sleat, in Skye, on his tour in Italy. Sir James, though only in his early twenties, was known as ‘the Scottish Marcellus’, and was a renowned scholar and celebrity, who visited Voltaire and travelled with Laurence Sterne (qv). Sir James died in Italy in 1766, and the following year Ogilvie became tutor in the family of James Fitzgerald (qv), 1st duke of Leinster. At first he was simply responsible for the education of the older boys, Charles (1756–1810) and Edward Fitzgerald (qv), and their brothers, but as time went on, Emily (qv), duchess of Leinster, who was widowed in 1773, entrusted the management of her household at Blackrock to him. She came to rely on him, and to enjoy his company so much that there was considerable scandal in society about the relationship; it was even whispered that several of the youngest children of the duke of Leinster had actually been fathered by Ogilvie.
Matters came to a head when the duchess's eldest daughter married Charles Coote (qv), earl of Bellamont; he caused a scene at their wedding in August 1774, alleging the impropriety of his mother-in-law's life. His new wife, probably intimidated by Bellamont, supported him in his criticism, despite a formal denial issued by Emily's eldest son. Two months later, on 26 October 1774, Ogilvie and Lady Emily were married at Toulouse, France, by a Mr Ellison, FTCD. She had informed her closest relatives in advance. Although the marriage must have seemed like a serious misalliance to the Fitzgeralds and the Lennoxes, who were among the proudest and most aristocratic families in the two kingdoms, they immediately rallied to support her. Once the initial shock and awkwardness of Ogilvie's new status were overcome, the family presented a united front and faced down the gossip and criticism. Emily's sister, Lady Louisa Conolly (qv), wrote to her: ‘You hurt your rank in the world, that is all that you do, and if you gain happiness by it, I am sure you make a good exchange’ (quoted in Fitzgerald, 147). For economic reasons, as well as to avoid social difficulties, Ogilvie and his household stayed in France for several years until in 1779 they travelled to England, and in 1781 to Ireland.
In February 1781 Ogilvie was elected MP for Gorey, and in the general election of 1783 MP for Ballyshannon, which belonged to Lady Emily's brother-in-law, Thomas Conolly (qv). After only a year in parliament, Ogilvie, a strong supporter of whig policies and undoubtedly ambitious for preferment, drew up a plan for a federal union of Ireland with England, which he submitted on 20 May 1782 to the lord lieutenant, the duke of Portland (qv). Ogilvie's seventeen articles were carefully thought out, recommending that England should have responsibility for external affairs, while the Irish legislature would have independent control of Irish matters, and he also suggested free trade between the countries. Portland was enthusiastic, but the plan failed to find support. Ogilvie was said to have written an able pamphlet in 1785 attacking Pitt's commercial propositions, and he also opposed them with his maiden speech in parliament. Opposition to the propositions was such that they were effectively thrown out in August 1785. Ogilvie was an MP until 1790; he did not enter parliament again, but is said to have been opposed to the union of 1800. In April 1798 he travelled from England to urge his stepson Lord Edward Fitzgerald to abandon the leadership of the revolutionary United Irishmen; the family hoped that Edward would agree to emigrate to America. Ogilvie went to see Lord Clare (qv), who offered to facilitate the young man's departure. In a last meeting with his former pupil, Ogilvie was unable to convince him to turn away from his revolutionary plans, and they parted in tears; their relationship had been deeply affectionate.
In 1806 the Ogilvies bought an estate at Ardglass, Co. Down, which had been in Fitzgerald hands for centuries, in a family arrangement by which the personal debts of the owner, Lord Charles Fitzgerald, Lady Emily's son, were discharged. Ogilvie subsequently expended considerable time, effort, and money on improvements in the area. After the death (27 March 1814) of his wife, Ogilvie went to live in Ardglass. He supervised the exploitation of granite quarries, and from 1809 oversaw major developments of the town's harbour, receiving a government grant to help build a pier 3,000 ft (914 m) long. His improvements brought the town long-lasting prosperity as an important fishing port, and he also provided baths, a dispensary, land for the catholic chapel, and a lighthouse. His surname was given as a Christian name in Ardglass families for many years, suggesting that he was greatly respected there. Ogilvie was an unusual man, at least for that period, in that he enjoyed manual labour in his garden, and himself nursed the children in the family when they were ill. He had a lively mind and an affectionate nature, but contemporaries often described him as morose and overbearing, particularly if they did not know him well.
He and Lady Emily had two daughters who survived to adulthood, and a child who died young. One of the daughters inherited the Ardglass estate after Ogilvie's death there on 18 November 1832, and descendants owned the estate for several generations.