According to Wikipedia: "Ernst Theodor Wilhelm Hoffmann (January 24, 1776 - June 25, 1822), better known by his pen name E.T.A. Hoffmann (Ernst Theodor Amadeus Hoffmann), was a German Romantic author of fantasy and horror, a jurist, composer, music critic, draftsman and caricaturist. He is the subject and hero of Jacques Offenbach's famous but fictional opera The Tales of Hoffmann.
Hoffmann's stories were tremendously influential in the 19th century, and he is one of the key authors of the Romantic movement."