"The Castle of Otranto", by Horace Walpole, published in 1764, is generally viewed as the first Gothic novel and it is often said to have founded the horror story as a legitimate literary form.

It tells the story of Manfred, the prince of Otranto, who is keen to secure the castle for his descendants in the face of a mysterious curse. The novel begins with the death of Manfred’s son, Conrad, who is crushed to death by an enormous helmet on the morning of his wedding to the beautiful princess Isabella. Faced with the extinction of his line, Manfred vows to divorce his wife and marry the terrified Isabella himself. The Castle of Otranto blends elements of realist fiction with the supernatural and fantastical, laying down many of the plot devices and character-types that would become typical of the Gothic: secret passages, clanging trapdoors, hidden identities and vulnerable heroines fleeing from men with evil intent. The novel was a success all over Europe, and the poet Thomas Gray commented in a letter to Walpole that it made ‘some of us cry a little, and all in general afraid to go to bed o’nights.’