Édouard Viénot was a successful society portrait painter with a studio at 92 rue de la Victoire, Paris.
Viénot is probably to be identified with "Le chevalier Viennot" who was active as a portrait painter in London in 1826 and 1827, when he had an address at 20 York Street, Portman Square.
From this address he exhibited two paintings at the Royal Academy in 1826 (Miss Paton of Covent Garden Theatre and Sir Robert Shaw, Bart., of Dublin) and three paintings at the Society of British Artists (now the Royal Society of British Artists) in 1827 (Portrait of Miss Paton, presumably the same as the Royal Academy picture, Portrait of Madame Viennot, presumably the artist's wife or mother, and Portrait of the Marchioness of Downshire).
Louis Hersent (1777-1860) was a gold medallist at the Salon of 1806, elected a member of the Institut 1822, and appointed professor at the Ecole des Beaux-Arts 1825.
Viénot did some portraits for different Spanish families established in South America during that period.