The Castle of Otranto is a 1764 novel by Horace Walpole. It is generally regarded as the first gothic novel, initiating a literary genre, which would become extremely popular in the later 18th century and early 19th century. Thus, Walpole, by extension, is arguably the forerunner to such authors as Charles Maturin, Ann Radcliffe, Bram Stoker, Edgar Allan Poe and Daphne du Maurier, with his usage of elements of terror, suspense and references to supernatural powers to catch the reader.
The Castle of Otranto tells the story of Manfred, lord of the castle, and his family. The book begins on the wedding-day of his sickly son Conrad and princess Isabella. Shortly before the wedding, however, Conrad is crushed to death by a gigantic helmet that falls on him from above. This inexplicable event is particularly ominous in light of an ancient prophecy. Soon the castle is to be haunted by betrayal, adultery and even murder.