She belonged to the prominent Salusbury family of Anglo-Welsh landowners, and married firstly a wealthy brewer, Henry Thrale, with whom she had 12 children, then a music teacher, Gabriel Mario Piozzi.

"[2] After her father had gone bankrupt in an attempt to invest in Halifax, Nova Scotia, Hester married the rich brewer Henry Thrale on 11 October 1763, at St Anne's Chapel, Soho, London.

Due to her husband's financial status, she was able to enter London society, as a result of which she met Samuel Johnson, James Boswell, Bishop Thomas Percy, Oliver Goldsmith, and other literary figures, including the young Frances Burney, whom she took with her to Gay Street, Bath.

[6] Frances, the wife of Sir Lynch's son Robert "found Johnson, despite his rudeness, at times delightful, having a manner peculiar to himself in relating anecdotes that could not fail to attract old and young.

[9] Frances Burney, in her diary, describes the conversations at several of Thrale's soirées, including one in 1779 about a young woman named Sophy Streatfeild (1755–1835), a daughter of Henry Streatfeild,[10] who was a favourite of Mr Johnson and Mr Thrale, rather to the chagrin of Hester, who commented that Sophy "had a power of captivation that was irresistible... her beauty joined to her softness, her caressing manners, her tearful eyes, and alluring looks, would insinuate her into the heart of any man she thought worth attacking.

"[11] The touch of jealousy here is further revealed in Thrale's remarking (after another of her male guests had professed devotion to Miss Streatfeild and the desire to "soothe" her): "I would ensure her power of crying herself into any of your hearts she pleased.

She complained: "I see the English newspapers are full of gross Insolence towards me," with one commenting how Thrale could not have imagined "his wife's disgrace, by eventually raising an obscure and penniless Fiddler into sudden Wealth.

The levelling marriage also earned her the disapproval of Burney (who would herself marry in 1793 the impoverished, Catholic émigré Alexandre D'Arblay) and her cousins the Cottons.

Thrale and Piozzi subsequently left England to travel in Europe for three years, especially in Italy and often following traditional routes of the Grand Tour.

[18] Thrale retired to Brynbella, a newly built country house on her Bach y Graig estate in the Vale of Clwyd, near Tremeirchion in north Wales in 1795.

[17] Thrale also wrote Observations and Reflections made in the Course of a Journey through France, Italy, and Germany (1789), which describes her travels during her honeymoon with Piozzi.

'"[19] A lexicographer in her own right, Mrs Piozzi's British synonymy, or, An attempt at regulating the choice of words in familiar conversation was published in 1794 by G. G. & J. Robinson of London, ten years after Dr Johnson's death.

10 (now 20) Sion Row, Clifton, Bristol, of complications after a fall, and was buried on 16 May 1821 near Brynbella in the churchyard of Corpus Christi Church, Tremeirchion, next to Piozzi.

Samuel Beckett drew on Thrale's diaries and Anecdotes to dramatize her and Johnson's relationship in one of his earliest plays, Human Wishes.