Hyacinthe-Gabrielle Wellesley, Marchioness Wellesley (1766 – 7 November 1816), formerly Hyacinthe Gabrielle Fagan and also known as Hyacinthe Gabrielle Fagan, was a French actress who became the mistress, and later the wife, of Richard Wellesley, 1st Marquess Wellesley of Norragh.
She was born as Hyacinthe-Gabrielle Roland in Paris, the daughter of Pierre Roland and Hyacinthe Gabrielle Varis.
Wellesley, the son of Garret Wesley, 1st Earl of Mornington, met Roland at the Palais Royal where she was an actress. She spoke no English, and they lived together for some years without marrying. He succeeded as 2nd Earl of Mornington in 1781.
They married on 29 November 1794 at St George's, Hanover Square, London, Following their marriage, she became Countess of Mornington, but remained a social outcast. Even the easy-going Elizabeth Lamb, Viscountess Melbourne refused to call on her, and scolded her daughter-in-law Lady Caroline Lamb severely for doing so.
Prior to their marriage, they had three sons and two daughters:
- Richard Wellesley (1787–1831), a member of parliament
- Anne Wellesley (1788–1875), who married firstly Sir William Abdy, 7th Baronet, and secondly Lieutenant-Colonel Lord Charles Bentinck
- Hyacinthe Mary Wellesley (1789–1849), who married Edward Littleton, 1st Baron Hatherton
- Gerald Wellesley (1792–1833), who served as the East India Company's resident at Indore.
- Rev. Henry Wellesley (1794–1866), Principal of New Inn Hall, Oxford.
Through their daughter Anne, Wellesley and his wife are great-great-great grandparents to Queen Elizabeth II.
In the course of their marriage, Wellesley also had at least two other illegitimate sons by another mistress, Elizabeth Johnston. In 1797, when the earl was obliged to travel to India in his capacity as Governor General, Hyacinthe did not accompany him, although he tried repeatedly to persuade her. There is some evidence that she was already seeking a legal settlement prior to his departure. In 1799 the earl was created Marquess Wellesley, making his wife a marchioness.
By 1801, her letters were accusing him both of infidelity with another Frenchwoman, Madame de Cocrement, and of neglect of his family. On the earl's return to Britain, he purchased Apsley House as a family home, but the couple quickly became estranged and he took another mistress. They formally separated in 1810, and she left the house, to live first in Grosvenor Square and then in Great Cumberland Place.
On 29 October 1825, some years after Hyacinthe's death, the earl married the widowed Marianne (Caton) Patterson (died 1853), a granddaughter of Charles Carroll of Carrollton, the last surviving signatory of the United States Declaration of Independence. Marianne was warned by her brother-in-law, Arthur Wellesley, 1st Duke of Wellington, not to marry his brother because of Hyacinthe's children, whom he called "The Parasites".
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- Joanne Major, Sarah Murden. "A Right Royal Scandal: Two Marriages That Changed History". Retrieved 25 April 2017.
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