Georges-Trevor-Douglas-Bernard d'Harcourt-Olonde (4 November 1808 - 30 November 1883) was a French aristocrat and a 19th-century diplomat. Formally styled marquis d'Harcourt, he served as French Ambassador to London from 1875 until 1879.
Of Anglo-Norman descent, he was the second son of Amédée Louis André Marie Charles François, marquis d'Harcourt (1771–1831) by his wife Elizabeth Harcourt (1771–1846), of Pendley Manor, Hertfordshire.
On 5 August 1841, he married Jeanne-Paule de Beaupoil (1817–1893), daughter of Louis-Clair, comte de Sainte-Aulaire and Louise Charlotte Victoire, daughter of Nicolas de Grimoard de Beauvoir du Roure de Beaumont, comte de Brison. They had seven children:[1]
His elder brother William marquis d'Harcourt-Olonde married, in 1837, Elizabeth Georgiana Cavendish, daughter of General The Hon. Henry Cavendish MP, while his sister, Marie-Augusta, became Duchess of Castries, wife of Charles de La Croix, duc de Castries.