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, with authors such as Charles Maturin, Ann Radcliffe, Bram Stoker, Edgar Allan Poe and Daphne du Maurier.

Horatio Walpole, 4th Earl of Orford (24 September 1717–2 March 1797), also known as Horace Walpole, was an English art historian, man of letters, antiquarian and Whig politician. He built Strawberry Hill House in Twickenham, south-west London, reviving the Gothic style some decades before his Victorian successors. His literary reputation rests on his Gothic novel, The Castle of Otranto and his Letters, which are of significant social and political interest. He was the son of the first Prime Minister, Sir Robert Walpole. As he was childless, his barony descended to his cousin of the same surname, who was created the new Earl of Orford.