H. P. Lovecraft

From The Yellow Site

Lovecraft was influenced by Chamber's book, which he had read in his youth, to include a reference to The Yellow Sign in his short story "The Whisperer in Darkness" (1931), one of his seminal Cthulhu Mythos stories. August Derleth further developed this connection and tied the King in Yellow to Hastur. In later mythos materials, the King is an avatar of Hastur, so named from his appearance as a thin, floating man covered in tattered yellow robes. Lovecraft also borrowed Chamber's method of only vaguely referring to supernatural events, entities, and places, thereby allowing the reader to imagine the horror for themselves.