In 1814 he exhibited his "Tam O'Shanter", and in 1816 he won a prize for his "Battle of Ligny". In 1817 he exhibited his "Battle of Marston Moor" and was made associate of the Royal Academy, and in 1820 he was elected Academician. Cooper, although ill-educated, was a clever and conscientious artist; his colouring was somewhat flat and dead, but he was a master of equine portraiture and anatomy, and had some antiquarian knowledge. He had a special fondness for Cavalier and Roundhead pictures.