
TheCthulhu Mythos is amythopoeia and ashared universe, originating in the works of Americanhorror writerH. P. Lovecraft. The term was coined byAugust Derleth, a contemporary correspondent andprotégé of Lovecraft, to describe the settings, tropes, and lore employed by Lovecraft and his literary successors. The name "Cthulhu" derives from the central creature in Lovecraft's seminal short story "The Call of Cthulhu", first published in thepulp magazineWeird Tales in 1928.[1]
Richard L. Tierney, a writer who also wrote Mythos tales, later applied the term "Derleth Mythos" to distinguish Lovecraft's works from Derleth's later stories, which modify key tenets of the Mythos.[2][3] Authors ofLovecraftian horror in particular frequently use elements of the Cthulhu Mythos.[4]: viii–ix

In his essay "H. P. Lovecraft and the Cthulhu Mythos",Robert M. Price described two stages in the development of the Cthulhu Mythos. Price called the first stage the "Cthulhu Mythos proper". This stage was formulated during Lovecraft's lifetime and was subject to his guidance. The second stage was guided by August Derleth who, in addition to publishing Lovecraft's stories after his death, attempted to categorize and expand the Mythos.[5]: 8 [6]: 5
An ongoing theme in Lovecraft's work is the complete irrelevance of mankind in the face of the cosmic horrors that apparently exist in the universe. Lovecraft made frequent references to the "Great Old Ones", a loose pantheon of ancient, powerfuldeities from space who once ruled the Earth and have since fallen into a deathlike sleep.[4]: viii While these monstrous deities were present in almost all of Lovecraft's published work (his second short story "Dagon", published in 1919, is considered the start of the Mythos), the first story to really expand the pantheon of Great Old Ones and its themes is "The Call of Cthulhu", which was published in 1928.
Lovecraft broke with other pulp writers of the time by having his main characters' minds deteriorate when afforded a glimpse of what exists outside their perceived reality. He emphasized the point by stating in the opening sentence of the story that "The most merciful thing in the world, I think, is the inability of the human mind to correlate all its contents."[7]
WriterDirk W. Mosig noted that Lovecraft was a "mechanistic materialist" who embraced the philosophy ofcosmic indifferentism and believed in a purposeless, mechanical, and uncaring universe. Human beings, with their limited faculties, can never fully understand this universe, and thecognitive dissonance caused by this revelation leads to insanity, in his view.[8][9]
There have been attempts at categorizing this fictional group of beings. Phillip A. Schreffler argues that by carefully scrutinizing Lovecraft's writings, a workable framework emerges that outlines the entire "pantheon"—from the unreachable "Outer Ones" (e.g.,Azathoth, who occupies the centre of the universe) and "Great Old Ones" (e.g., Cthulhu, imprisoned on Earth in the sunken city ofR'lyeh) to the lesser castes (the lowly slaveshoggoths and theMi-Go).[10]
David E. Schultz said Lovecraft never meant to create a canonical Mythos but rather intended his imaginary pantheon to serve merely as a background element.[11]: 46, 54 Lovecraft himself humorously referred to his Mythos as "Yog Sothothery" (Dirk W. Mosig coincidentally suggested the termYog-Sothoth Cycle of Myth be substituted forCthulhu Mythos).[12][13] At times, Lovecraft even had to remind his readers that his Mythos creations were entirely fictional.[9]: 33–34
The view that there was no rigid structure is expounded upon byS. T. Joshi, who said
Lovecraft's imaginarycosmogony was never a static system but rather a sort of aesthetic construct that remained ever adaptable to its creator's developing personality and altering interests. ... There was never a rigid system that might be posthumously appropriated. ... The essence of the mythos lies not in a pantheon of imaginary deities nor in a cobwebby collection of forgotten tomes, but rather in a certain convincing cosmic attitude.[14]
Price said Lovecraft's writings could at least be divided into categories and identified three distinct themes: the "Dunsanian" (written in a similar style asLord Dunsany), "Arkham" (occurring in Lovecraft's fictionalizedNew England setting), and "Cthulhu" (the cosmic tales) cycles.[6]: 9 Writer Will Murray noted that while Lovecraft often used his fictional pantheon in the stories he ghostwrote for other authors, he reserved Arkham and its environs exclusively for those tales he wrote under his own name.[15]
Although the Mythos was not formalized or acknowledged between them, Lovecraft did correspond, meet in person, and share story elements with other contemporary writers includingClark Ashton Smith,Robert E. Howard,Robert Bloch,Frank Belknap Long,Henry Kuttner,Henry S. Whitehead, andFritz Leiber—a group referred to as the "Lovecraft Circle".[16][17][18]
For example, Robert E. Howard's characterFriedrich Von Junzt reads Lovecraft'sNecronomicon in the short story "The Children of the Night" (1931), and in turn Lovecraft mentions Howard'sUnaussprechlichen Kulten in the stories "Out of the Aeons" (1935) and "The Shadow Out of Time" (1936).[6]: 6–7 Many of Howard's original uneditedConan stories also involve parts of the Cthulhu Mythos.[19]
Price denotes the second stage's commencement with August Derleth, with the principal difference between Lovecraft and Derleth being the latter's (deeply debated) use ofhope and development of the idea that the Cthulhu Mythos essentially represented a struggle betweengood and evil.[5]: 9
Derleth is credited with creating the "Elder Gods". He stated:
As Lovecraft conceived the deities or forces of his mythos, there were, initially, the Elder Gods.... These Elder Gods were benign deities, representing the forces of good, and existed peacefully...very rarely stirring forth to intervene in the unceasing struggle between the powers of evil and theraces of Earth. These powers of evil were variously known as the Great Old Ones or the Ancient Ones....[20]
Price said the basis for Derleth's system is found in Lovecraft: "Was Derleth's use of the rubric 'Elder Gods' so alien to Lovecraft's inAt the Mountains of Madness? Perhaps not. In fact, this very story, along with some hints from "The Shadow over Innsmouth", provides the key to the origin of the 'Derleth Mythos'. For inAt the Mountains of Madness is shown the history of a conflict betweeninterstellar races, first among them the Elder Ones and the Cthulhu-spawn."[21]
Derleth said Lovecraft wished other authors would actively write about the Mythos rather than treat it as a discrete plot device within Lovecraft's own stories.[11]: 46–47 Derleth expanded the boundaries of the Mythos by including any passing reference to another author's story elements by Lovecraft as part of the genre. Just as Lovecraft made passing reference to Clark Ashton Smith'sBook of Eibon, Derleth in turn added Smith'sUbbo-Sathla to the Mythos.[6]: 9–10
Derleth also attempted to connect the deities of the Mythos to theclassical elements, creating new beings representative of certain elements to legitimize his system of classification. He created "Cthugha" as a sort of fire elemental when a fan, Francis Towner Laney, complained that he had neglected to include the element in his schema. Laney, the editor ofThe Acolyte, had categorized the Mythos in an essay that first appeared in the Winter 1942 issue of the magazine.
Impressed by the glossary, Derleth asked Laney to rewrite it for publication in the Arkham House collectionBeyond the Wall of Sleep (1943).[22] Laney's essay ("The Cthulhu Mythos") was later republished inCrypt of Cthulhu #32 (1985). In applying the elemental theory to beings that function on a cosmic scale (e.g.,Yog-Sothoth) some authors created a fifth element that they termedaethyr.[citation needed]
| Air | Earth | Fire | Water |
|---|---|---|---|
| Hastur Ithaqua* Nyarlathotep Zhar and Lloigor* | Cyäegha Nyogtha Shub-Niggurath Tsathoggua | Aphoom-Zhah Cthugha* Yig | Cthulhu Dagon Ghatanothoa Mother Hydra Zoth-Ommog |
| * Deity created by Derleth | |||
A number of fictionalcults dedicated to "malevolent supernatural entities" appear in the Cthulhu Mythos, the loosely connected series of horror stories written by Lovecraft and other writers inspired by his creations.[23] These fictional cults have, in some ways, taken on a life of their own beyond the pages of Lovecraft's works. According to author John Engle, "The very real world of esoteric magical and occult practices has adopted Lovecraft and his works into its canon, which have informed the ritual practices, or even formed the bedrock, of certain cabals and magical circles".[24]
The Cthulhu Mythos of H. P. Lovecraft is considered to have been highly influential for thespeculative fiction genre. It has been called "the officialfictional religion of fantasy, science fiction, and horror, a grab bag for writers in need of unthinkably vast, and unthinkably indifferent, eldritch entities".[25]
Sollasina cthulhu, an extinctophiocistioidechinoderm, is named after the Cthulhu Mythos.[26]
Yogsothoth is a genus of centrohelid protists.