Cthulhu Mythos
The Bran Mak Morn stories are connected to the Cthulhu Mythos and take place in the same fictional universe. Twice in Worms of the Earth mention is made of the black gods of R'lyeh, resting place of Cthulhu, creation of H. P. Lovecraft, a friend and correspondent of Howard. In the earliest extant copy of Worms of the Earth mention of Cthulhu himself is made by name although this was later changed to Nameless Gods in the final edition. Also mentioned in the same story is the water monster Dagon, a real-world Philistine god mentioned in a fictional context in some stories by Lovecraft. Lovecraft himself references Bran Mak Morn in his short story "The Whisperer in Darkness".
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