Excellent post on Machen on Anthony Brockway's Babylon Wales, a fine blog on the stranger byways of Welsh popular culture.
"Welsh literary critics have largely ignored him or unfairly Uncle Tom-ed him (see Stephen Knight's jaw-dropping sidestep of Machen's work in A Hundred Years of Fiction). Rather than being a literary Uncle Tom you could quite easily - if you chose to do such a thing - make a case for Machen being a highly subversive Welsh writer. In many of his stories the English/rational/scientific is undermined by the Welsh/irrational/primitive. And it is the latter grouping that Machen most certainly identified with.
The problem with Machen for Welsh critics is that he doesn't fit easily into dominant social realist/nationalist/post-colonial readings of Welsh writing in English. He is a one-off, an outsider. Add to this a snooty attitude from academia towards genre fiction in general (horror stories aren't real writing are they?) and you begin to understand why Machen's work has slipped into the margins in Wales."