Equally, it is hard to identify where, precisely, the Mythos begins, since one cannot be certain when Lovecraft devised the sequence. L. Sprague de Camp identifies The Nameless City (1921) as the first story, while others opt for Dagon, written four years earlier. Not unreasonably, Robert M. Price favours the 1926 tale The Call of Cthulhu. After all, how can you have a Cthulhu Mythos without a Cthulhu? To complicate matters further, H.P.L. brought several of his earlier works within the cycle’s continuity. For instance, the race known as the Deep Ones are tied to the Mythos through the 1931 story, The Shadow over Innsmouth, but the Deep Ones make their first appearance in Dagon. Furthermore, the death of Dagon’s narrator is mentioned in The Call of Cthulhu. Lovecraft had a horror of all seafood, and it is interesting to note how many of his monsters are aquatic in origin.

H.P.L.’s works, published in several amateur publications prior to 1923, came to the attention of J. C. Henneburger, publisher of Weird Tales, a pulp magazine edited at the time by Edwin F. Baird. Baird contacted Lovecraft, and the writer’s friends encouraged him to submit material to the publication, but H.P.L. was unenthusiastic, considering the life of a freelance author at odds with his status as self-proclaimed gentleman. Nevertheless, he sent several stories to Baird with a covering letter, all but begging him not to purchase them. Baird must have had a keen sense of humour, for he published the letter in the magazine along with an announcement that Dagon would follow in the next issue. Thus the fame of both H. P. Lovecraft and Weird Tales Magazine became inextricably intertwined.

Lovecraft often experienced extraordinarily vivid dreams, which he was occasionally able to use in his writing. So it was with The Nameless City, the first of his works to make mention of Abdul Alhazred, later an important figure in the Mythos as the author of the fabled Necronomicon, although he is not identified as such here. Who was Alhazred? None other than Lovecraft himself. At the age of five, he enjoyed playing at being an Arab, and a relative suggested the name to him.

Alhazred’s chilling couplet:

That is not dead which can eternal lie,

And with strange aeons even death may die,

is repeated in The Call of Cthulhu.

The Nameless City’s equally nameless narrator refers in passing to a Lovecraft story written two years earlier, The Doom That Came to Sarnath, and this particular story is in turn mentioned in At the Mountains of Madness (1931). One of H.P.L.’s earliest writing influences, Lord Dunsany, is referenced here, as well as in The Case of Charles Dexter Ward.

As a youth, Lovecraft was a great fan of Sir Arthur Conan Doyle’s Sherlock Holmes stories. In fact, he refers to the famous mystery writer in The Unnamable (1922). The inspiration for Lovecraft’s story The Hound, written that same year, is fairly obvious, but unlike the beast of the Baskervilles this creature does indeed prove to be of supernatural origin. The Holmes/Lovecraft connections continue: in 1996, a version of the fabled ‘missing’ Holmes adventure The Giant Rat of Sumatra appeared, attributed to Lovecraft, but actually written by Paula Volsky, and in 2003 a collection of stories bringing Holmes face to face with the Old Ones was published as Shadows Over Baker Street.