Around 1927 or 1928, Lovecraft began to come into his own as a writer.  Of course, the exact time is subject to interpretation.  “The Colour Out of Space,” written in 1927, is generally regarded as a mature work.  “The Dunwich Horror,” written in 1928, may be considered either mature or transitional. Lovecraft himself did not consider “The Dunwich Horror” to be a mature work.  “The Strange Case of Charles Dexter Ward,” started in 1927 and completed in 1928, can probably be classified as transitional, though that is very much a matter of opinion.  Every story after that point can  safely be considered a mature work.

Many of the arguments that can be made against Lovecraft's work as a whole do not apply to his work after 1928.  Lovecraft's mature works are finally free of the heavy influence of Poe (and others) that caused much of his earlier work to appear derivative.  He developed his own unique voice at that point. The quality of the writing is impeccable.  This is Lovecraft at his best.  It is also largely free of the racist qualities that tainted much of his earlier work.  Unfortunately, there is not very much of it, as H. P. Lovecraft died of intestinal cancer in 1937, at the age of 46, having just come into his own as a writer.  Lovecraft only wrote ten pieces after “The Dunwich Horror.”

It should be noted that Lovecraft did produce some very good work prior to 1927.    The nightmarish prose poem “Nyarlathotep” and the amusing if atypical “The Cats of Ulthar” were written in 1920.  “The Music of Erich Zann” and “The Other Gods” were both written in 1921.  “The Call of Cthulhu,” Lovecraft's most popular story, was written in 1926.