John Freind (1675–1728) had a controversial career. Although a popular physician, he sparked a pamphlet war by publishing unpopular ideas about hydraulic physiology. He was suspected of participating in the 1722 so-called ‘Bishop’s plot’, a political reaction to England’s trading policies in South America in the eighteenth century. Freind was imprisoned in the Tower of London, and only released because his friend Dr Richard Mead refused to treat the Prime Minister, Sir Robert Walpole, unless Freind was liberated. After his release, Freind was appointed physician to the Prince of Wales, and then to Queen Caroline.

Freind was an accomplished classical scholar before he studied medicine, and translated into English Ovid’s 'Metamorphoses', and wrote many letters and treatises in Latin, including his 'Emmenologia', a treatise on menstruation.