Elizabeth Cavendish, Duchess Of Devonshire

Elizabeth Christiana Cavendish, Duchess of Devonshire (née Hervey), was born on 13 May 1758 in Horringer, Suffolk, England. She was the daughter of Frederick Hervey, who later became the 4th Earl of Bristol and served as Bishop of Derry, and Elizabeth Davers, the daughter of Sir Jermyn Davers, 4th Baronet. She had three brothers, including John, Lord Hervey, and Frederick, 1st Marquess of Bristol, and two sisters, Lady Mary Erne and Louisa, Countess of Liverpool.

In 1776, she married Irishman John Thomas Foster, born in 1747. Foster was a first cousin of John Foster, Baron Oriel, the last Speaker of the Irish House of Commons, and Bishop William Foster. Their marriage produced three children: two sons, Frederick (b. 3 October 1777) and Augustus John Foster (b. 1780), and a daughter, Elizabeth, who was born prematurely on 17 November 1778 and died eight days later. After her husband's succession to the earldom in 1779, Elizabeth was styled as Lady Elizabeth Foster. The couple resided at Ickworth House in Suffolk after 1779. The marriage was reportedly not successful, and the couple separated within five years amidst reports of an "intrigue" between Foster and their maid, Madam Wagniere. Foster retained custody of their sons, who were not allowed to see Elizabeth for fourteen years.

In May 1782, Elizabeth Met the Duke and Duchess of Devonshire in Bath and became close friends with Georgiana Cavendish, Duchess of Devonshire. She subsequently became involved in a close relationship with Georgiana and her husband, William Cavendish, 5th Duke of Devonshire, forming a triad that lasted approximately twenty-five years. During this period, she bore two illegitimate children by the duke: a daughter, Caroline St Jules, and a son, Augustus Clifford, later known as the 1st Baronet. These children were raised at Devonshire House alongside the duke’s legitimate offspring from his marriage to Georgiana.

Following Georgiana's illness and death in 1806, Elizabeth married William Cavendish, 5th Duke of Devonshire, in 1809, thereby becoming the Duchess of Devonshire. The duke died two years later in 1811. Elizabeth is believed to have had affairs with several men, including Cardinal Ercole Consalvi, John Sackville, 3rd Duke of Dorset, Count Axel von Fersen, Charles Lennox, 3rd Duke of Richmond, and Valentine Quin, 1st Earl of Dunraven and Mount-Earl. Quin served as her traveling physician in Rome in December 1820 and remained with her during her fatal illness in March 1824.

She maintained a correspondence with Madame de Staël, the French author, from approximately 1804 onward. Elizabeth Christiana Cavendish died on 30 March 1824, on the same date as the death of Georgiana Cavendish, Duchess of Devonshire. Her personal letters and relationships are documented in various biographical and historical sources, including "The Two Duchesses" edited by Vere Foster, her grandson, and works by authors such as Brian Masters and Amanda Foreman.

Her life has been depicted in media; notably, she was portrayed by Hayley Atwell in the 2008 film "The Duchess."

Children:

- With John Thomas Foster:

- Frederick (3 October 1777 – 1853)

- Elizabeth (17 November 1778 – 25 November 1778)

- Sir Augustus Foster, 1st Baronet (1780–1848)

- With William Cavendish, 5th Duke of Devonshire:

- Caroline Rosalie Adelaide (1785–1830), married The Hon. George Lamb

- Sir Augustus William James Clifford, 1st Baronet (1788–1877), married Albina Jane Hobart