[4] Cthulhu Mythos scholar Robert M. Price claims the irregular sonnet "The Kraken",[5] published in 1830 by Alfred Tennyson, was a major inspiration, since both reference a huge aquatic creature sleeping for an eternity at the bottom of the ocean and destined to emerge from its slumber in an apocalyptic age.

[6] S. T. Joshi and David E. Schultz cited other literary inspirations: Guy de Maupassant's "The Horla" (1887), which Lovecraft described in Supernatural Horror in Literature as concerning "an invisible being who...sways the minds of others, and seems to be the vanguard of a horde of extraterrestrial organisms arrived on Earth to subjugate and overwhelm mankind"; and Arthur Machen's "The Novel of the Black Seal" (1895), which uses the same method of piecing together of disassociated knowledge (including a random newspaper clipping) to reveal the survival of a horrific ancient being.

Joshi says that 'Merritt's mention of a "moon-door" that, when tilted, leads the characters into a lower region of wonder and horror seems similar to the huge door whose inadvertent opening by the sailors causes Cthulhu to emerge from R'lyeh'.

[13] The deceased narrator, Francis Wayland Thurston, recounts his discovery of notes left behind by his grand-uncle, Brown University linguistic professor George Gammell Angell, after his death in the winter of 1926–27.

The sculptor, a Rhode Island art student named Henry Anthony Wilcox, based the work on delirious dreams of "great Cyclopean cities of titan blocks and sky-flung monoliths."

More notes discuss a 1908 meeting of an archeological society in which New Orleans police official John Raymond Legrasse asks attendees to identify a statuette of unidentifiable greenish-black stone resembling Wilcox's sculpture.

Thurston discovers a 1925 article from an Australian newspaper which reports the discovery of a derelict ship, the Alert, of which second mate Gustaf Johansen is the sole survivor.

Johansen's widow provides Thurston with her late husband's manuscript, wherein the uncharted island is described as being home to a "nightmare corpse-city" called R'lyeh.

[18] Canadian mathematician Benjamin K. Tippett noted that the phenomena described in Johansen's journal may be interpreted as "observable consequences of a localized bubble of spacetime curvature", and proposed a suitable mathematical model.