The Gothic genre originated with Horace Walpole's 1765 book "The Castle of Otranto", which was very popular and spawned many imitators. Gothic works often featured bizarre or dark plots involving madness, insanity, and the supernatural. This tradition continues today in works like those of Neil Gaiman and Tim Burton that draw from Gothic literature. The term "Gothic" comes from Gothic architecture of the Middle Ages characterized by irregular shapes, grotesques, and lack of symmetry. Romanticism explored imagination and dreams while Gothic literature explored the darker side including nightmares, individual evil, and horrors hidden in nature. Major American Gothic writers included Edgar Allan Poe, Nathaniel Hawthorne, and Washington