The Hon. William Robert Spencer (1769-1834), facing left in red velvet coat, frilled lace cravat, powdered hair; tree background

William Robert, second son of Lord Charles Spencer (1740-1820) and Mary, sister of 5th Duke of St. Albans, and grandson of Charles, 3rd Duke of Marlborough (1706-1758), married Susan (d. 1834), widow of Count Spreti and daughter of Ralph Jenison Count von Walworth in 1791 and had issue.
Another version of this miniature, without identification of the sitter, is illustrated in the exhibition catalogue Secret Passion to Noble Fashion, Holburne Museum of Art, Bath, 1999, pp. 166-167, no. 68.