Daughter of Claude III de Beauharnais (1756-1819) and his first wife Gabrielle de Lezay-Marnézia – Claude III and Alexandre de Beauharnais (father of Eugène and Hortense) were first cousins, therefore Stéphanie and Eugène and Hortense were second cousins.
On the death of her mother, Stéphanie was brought up by the Englishwoman, Lady Bath. She was presented to the (still) Consular court in January 1804, and continued her education at Madame Campan's school for young ladies. Her beauty and coquettishness were renowned and she so much attracted the First Consul that Josephine was roused to jealousy and Caroline Bonaparte to hate. Napoleon married Stéphanie to the crown prince of Baden, Charles-Louis-Frédéric – treaty of alliance 17 February, 1806. The emperor adopted Stéphanie as his daughter on 3 March and the marriage was celebrated with great pomp 7-8 April. Napoleon gave her as her marriage dowry and trousseau 150,000 Francs and 500,000 Francs respectively. Despite a difficult marriage, she gave birth to at least five children, and after the restoration, her husband did not repudiate her, although he was placed under certain pressure to do so. Was Stéphanie the mother of Gaspard Hauser? Bapst, A la conquête de Bade (1930) thought so. J. Mistler, Gaspard Hauser, un drame de la personalité (1971) disagreed.
After the murder of Hauser in 1828, Stéphanie returned often during these dark years to France, finally seeing her fortunes rise with the accession of Napoléon-Louis, to whom she attached herself. She was to die in prosperity in Nice on 29 January 1860, loved and appreciated by all.
Sources: Fernand Beaucour, Revue du Souvenir Napoléonien, no. 258 (avril), 1971, pp. 44-45 Tulard, J. (ed.), Dictionnaire Napoléon, Paris: Fayard, 2000, s.v. Stéphanie de Beauharnais, p. 186. Sirjean, Dr Gaston, Encyclopédie généalogique des Maisons Souveraines du monde, Paris: Sirjean, 1959, 9 cahiers Grand Format, Cahier 9: les Bonaparte (lignée féminine)