I like speculative and weird fiction, particularly the work of China Mieville (which some would call "new weird fiction" to distinguish it from the weird fiction of the late 1800s and early 1900s). Weird fiction's been around since at least the Victorian era, and Edgar Allen Poe and especially H.P. Lovecraft are often held up as early practitioners--or in Poe's case an influence on early practitioners.
At the edges of this broad literary category there are places of overlap with the genres of fantasy, science fiction, and horror, too. Thus it is that weird fiction embraces a wide array of authorial perspectives, despite the fact that all weird fiction has one or more elements of the fantastical. For instance, Lovecraft's monsters and nighmarescapes are elements of his weird fiction that is decidedly pagan, dark, and pessimistic; yet, demonic possession, an orthodox view of Christ as God-man, and the real-world myth of the Holy Grail are elements of some of the novels of Charles Williams's weird fiction that is decidedly Christian, even vaguely evangelistic, and optimistic, including his works All Hallows' Eve and War In Heaven. But, I would not classify as weird fiction the Middle-Earth or Narnia books of Williams's fellow "Inklings," the most famous of that 1930s and 1940s Oxford literary circle that Williams led for a time: J.R.R. Tolkien and C.S. Lewis respectively. Tolkien's and Lewis's works are works of mythopoeic fantasy; they are attempts at a type of wholesale world-building: self-referential, complex fantasies supported by a network of invented mythic narratives influenced by largely Western--specifically Anglo-Saxon, Nordic, and Icelandic--real-world myths, and basically both heroic (never anti-heroic!) and epic in tone. What is more, Lewis's Narnia books, like Tolkien's novel The Hobbit, are intended primarily for young readers, and the vast majority of weird fiction is decidedly not for children--there are even works of classic weird fiction that arguably overlap with a late 1800's literary movement called the Decadent movement.
Weird fiction's influence can today be seen, not at all surprisingly, in recent cinema, too; for example, Guillermo del Toro's stunning achievement, Pan's Labyrinth (examine the website's wonderful section on del Toro's sketchbook; it's surely one reason the site won a 2007 Webby award) and Alfonso Cuarón's adaptation of P. D. James's The Children of Men. I eagerly await a film-maker's attempt to render cinematically China Mieville's world of Bas-Lag! I can only assume that a filmmaker has already acquired the rights to do so.
But, for my taste, weird fiction is sometimes too enthralled with the supernatural. Generally, I'm keen on a work of weird fiction, either "classic" or "new," in inverse relation to its emphasis on mysticism and spiritualism--and in the case of new weird fiction such emphases would include New Age claptrap. One reason I so admire Mieville's fiction is precisely because it avoids spiritualistic supernaturalism.
Thus it is that I'm conflicted about Arthur Machen, a founder of weird fiction. On one hand, I'm inclined to sing his praises as a rather unsung father of weird fiction. On the other hand, he wallows in the what I consider to be the literary muddy sludge of ghosty creepiness. That's why I love Machen's twisted fate in the controversy of the "Angels of Mons."
In short, Machen found himself later in his career, during the First World War after having published numerous supernaturalistic works, in the position of publicly insisting against erstwhile true-believers that a tale he wrote about avenging Anglo-ghosts miraculously appearing at the battle at Mons was fiction.
I can't tell the tale better than the summary on the website of Friends of Arthur Machen:
A month after the battle [at Mons, in August 1914,] Machen wrote a piece which was published in the Evening News, describing celestial archers from the days of Agincourt appearing in the sky, firing their arrows upon the Germans and averting defeat. Machen's story, "The Bowmen", was in essence a piece of patriotic wish-fulfillment; however, only a few weeks after publication he began to receive requests "from parish magazines" for details of his source for the story. He asserted that his only source was his own imagination....
[B]ut others insisted that, even if he had not recognized it as such, he had been vouchsafed a true vision. Fierce wartime censorship made it difficult to determine with any objectivity what had and hadn't happened at Mons, and Machen's opponents found, and published, evidence, based on hearsay, to prove that Angels really had appeared. None of the evidence for "Angels", or Bowmen, was very convincing, but the spiritual aspiration which underpinned these phenomena chimed with the hysterical national climate of 1914: eventually three books and many articles were written on the controversial subject of "The Angels of Mons".
In fact, the conditions of the first printing of Machen's story go some way to explain what arose. Under wartime reporting restrictions, the Evening Newshad taken to using focused accounts of battle from individual soldiers, which readers were expected to understand as true. Machen's story can be read as such an account. Moreover, though Machen had been a reporter for the paper for some time, he had never previously published fiction in its pages, and his piece wasn't labeled as fiction - in fact, misleadingly, another item clearly headed "Our Short Story" was printed on another page of the same issue. All of these factors no doubt helped to suggest that what Machen had written was not fiction.
It was ironic that Machen, who was by then a doughty champion of the mystical and spiritual view of human life, was forced out of honesty to take the materialist position, denying the reality of an occurrence whose truth he must have longed for.
(Images, UR: a depiction by Les Edwards of the tethered armada described in China Mieville's novel, The Scar; LR: a print, The Angels of Mons--I assume of the period and mass-produced--as seen on the website of the Penny family of New Zealand.)