Dubbed ‘The Phoenix’ by William Beckford, Hayter showed a pomposity that irritated his fellow artists, but he mixed freely with many aristocratic families. His unconventional domestic life (separated from his wife, yet living with his mistress) set him apart from official Academy circles: he was never elected to the Royal Academy. Hayter was most productive and innovative during the 1820s. George Agar-Ellis (later Lord Dover) commissioned the Trial of Queen Caroline in the House of Lords in 1820 (exh. Cauty's Great Rooms, 80-82 Pall Mall, 1823; London, National Portrait Gallery); painted on a large scale (2.33×2.66 m), Hayter's first (and most successful) contemporary history painting revealed a taste for high drama effectively realised. In the Trial of William, Lord Russell, in the Old Bailey in 1683 (1825; Woburn Abbey) Hayter celebrated John Russell's ancestry, in a work reminiscent of fashionable tableaux vivants of the country-house set. In 1826 Hayter settled in Italy. The Banditti of Kurdistan Assisting Georgians in Carrying off Circassian Women (untraced), completed in Florence for John Proby, 1st Earl of Carysfort (exhibited British Institution 1829), demonstrated Hayter's assimilation of the style and exotic subject-matter of contemporary French Romantic art. In 1827 his mistress, Louisa Cauty, died after poisoning herself with arsenic. Although it was apparently an accident, in a bid for attention, it was widely assumed that he had driven her to suicide, and he was forced by the scandal to move from Florence to Rome. By late 1828 he was in Paris, where his portraits of English society members (some exhibited at the Salon in 1831) were stylistically akin to the work of recent French portrait painters such as François Gérard. In 1831 Hayter returned to England. His grandiose plan to paint the first sitting after the passage of the Reform Bill resulted in his painting "Moving the Address to the Crown on the Opening of the First Reformed Parliament in the Old House of Commons, 5 February 1833" (1833–1843; London, N.P.G.), for which he executed nearly 400 portrait studies in oil. Hayter was an ardent supporter of the reform movement and this painting was not commissioned but to all intents and purposes a labour of love.