The Mysteries of Udolpho by Ann Radcliffe appeared in May of 1794. This work consists of four volumes with the last and most popular being The Mysteries of Udolpho. Set in 1584 in the south of France and northern Italy, the novel depcits the story of a young girl named Emily St. Aubert, complete with gloomy castle setting, the death of her parents, and supernatural terrors.  Often cited as the archetypal Gothic novel "The Mysteries of Udolpho appears prominently in Jane Austin's 1817 novel Northanger Abbey [in which] an impressionable young woman comes to see friends and acquaintances as Gothic villains and victims, with amusing results" (Mambrol, "Gothic Novels and Novelists").

Mambrol, Nasrullah. “Gothic Novels and Novelists.” Literary Theory and Criticism, 18 Mar. 2019, literariness.org/2019/03/11/gothic-novels-and-novelists/.