"The Thing on the Doorstep" (1937) is perhaps my all-time favorite horror story—one of H.P. Lovecraft's best pieces. One of the main characters is Edward Pickman Derby, who finds himself battling against the possession attempts of his wife Asenath Waite.
Somewhere, I seem to recall reading that Derby's character was inspired to a significant degree by that of Robert E. Howard. Later in his career, Lovecraft included quite a few homages to his peer authors in his stories. For example, "The Haunter of the Dark" (1935) is explicitly dedicated to the young Robert Bloch, and the protagonist is named Robert Blake. So I am trying to track down what might be known about a connection between Howard and Derby.
The Wikipedia page for the story suggests a number of individuals who may have influenced the Lovecraft's characterization of Edmund Derby: Lovecraft himself, for his secluded upbringing; Clark Ashton Smith, for his exotic and similarly titled poetry; and Frank Belknap Long, for his inability to grow a beard. There are also clear allusions to Howard's mythos writing, among other authors. However, nothing is mentioned about Howard being an inspiration for Derby's character. (I should note that the Wikipedia article, at present, also contains at least one glaring error. It dates Derby's death at the climax of the story to the year 1933, which is impossible since the town of Innsmouth was completely razed in 1928.)
I am not sure where I came across the theory connecting Howard and Derby, and I would like to know where I got it and what the evidence in support of it was. On my most recent rereading of the story, I noticed at least two clear similarities between the two. Derby is described as having "a juvenile chubbiness rather than the paunchiness of premature middle age," a description that Howard seems to answer to as well, at least in the one famous photograph of him.
A more poignant similarity also struck me. Both men were profoundly affected by the deaths of their mothers. Howard, unable to deal with his mother's death, killed himself; Derby's devastation after his mother's death starts him down the path of involvement with Asenath Waite that eventually led to his own early death. While the story was mostly written in 1933, the final version was not published until early 1937, after Howard's suicide, which may have been weighing on Lovecraft's mind in the latter half of 1936.