The Cthulhu Mythos is a shared fictional universe, based on the work of American horror writer H. P. Lovecraft. The term was first coined by August Derleth, a contemporary correspondent of Lovecraft, who used the name of the creature Cthulhu—a central figure in Lovecraft literature and the focus of Lovecraft’s short story “The Call of Cthulhu”—to identify the system of lore employed by Lovecraft and his literary successors. The writer Richard L.