At Publishers Weekly, Rose Fox has some spellbinding things to say about “The Genre Formerly Known as Horror”:
Horror became a publishing category–a genre–sometime after Fred Mustard Stewart and Ira Levin had shown that a horror novel could be both good fiction and hugely best-selling. The cause was a phenomenon named Stephen King. This is important, this understanding of King as a phenomenon. It’s something that the publishing world didn’t get. They saw the huge sales figures of Mr. King and determined that the well of horror must be bottomless and would make them wildly rich.
[Thanks to Andrew Porter for the link.]