In modern American media, the Pacific Northwest is the setting of much supernatural or weird fiction: Twilight, Twin Peaks, Gravity Falls, and many other stories. When and where does this trope begin? In what kind of media? Was it originally associated with a particular author or work?
In no other land, in modern times, have towns so absolutely died and disappeared, as in the old mining regions of California. It was a driving, vigorous, restless population in those days...And where are they now?
Scattered to the ends of the earth – or prematurely aged or decrepit – or shot or stabbed in street affrays – or dead of disappointed hopes and broken hearts – all gone, or nearly all – victims devoted upon the altar of the golden calf – the noblest holocaust that ever wafted its sacrificial incense heavenward.
-Mark Twain, "Roughing It"
Gothic literature tells our stories of "fear, failure, despair, nightmare, crime, disease, and madness". It uses the wild/erness of the darkly enchanted and dark forest to reflect the wilderness in humanity; it finds in the ruins of human construction a (literally) haunting past that is forever tantalizing but forever lost. Essentially, Gothic is everything America defines itself against. It's no wonder, then, that this dark mirror of the West grew up on both sides of the Atlantic along with that platonic ideal of western culture and imperialism, the American Dream.
When Europeans arrived on the East Coast, they found plenty of dark forest to embody their inner fears--but ruins were in short supply. S.T. Joshi suggests that 18th and early 19th century authors like Nathaniel Hawthorne turned to the Puritan past to create "historical ruins"--drawing on the Salem witch trials, but also the genocide against Native Americans. (/u/AncientHistory and I talk about how the "Native American burial ground" trope captures human fears of the wilderness always encroaching in this fun thread).
But European-colonized America didn't have to wait long to build and destroy its own ruins. The Civil War raging across the South "reduc[ed] the noble mansion to ashes, leaving only the skeleton chimneys standing, gaunt, grim, and ghastly, to mark the spot where had been a Southern home," wrote W.H. Peck as early as 1867. Charles Chestnutt's ex-slave narrator Julius visits a plantation house that "had been destroyed by fire many years before and there were few traces of it remaining – a crumbling brick pillar here and there, on which the sills of the house had rested, and the dilapidated, ivy-draped lower half of a chimney, of which the yawning, blackened fireplace bore mute witness of the vanished generations."
And it is in those ever-smoking, crumbling ruins of the South and of Southern Gothic that many of the earliest West Coast Gothic/weird fiction writers--Ambrose Bierce, W.C. Morrow--found their footing.
But as Martin Procházka points out, there was always a difference between the ruins of European Gothic and the ruins of American Gothic. In the crumbling castles and abbeys inherited from the Middle Ages, writers could tap into a sense of the sublime, of past greatness imbued with a certain spiritual power. The Lost Causers headlined above all by the United Daughters of the Confederacy worked overtime in the late nineteenth and early twentieth centuries to turn Southern ruins into spiritual ones that, perhaps, were not ruins at all (Gone with the Wind is a great example of this).
But up and down the Pacific coast, from San Francisco on northwards, writers were confronted with a new type of ruin: the ghost town. The term "ghost city" was coined in 1915, but it was "ghost town" that had caught on by 1922: smaller, scrappier, less civilized. By that point, the ghost town was firmly fixed in the American imagination as peculiarly and truly American ruins. And these are not sacred ruins, these are not sublime. As Mark Twain so eloquently observed, abandoned mining towns were the ghosts of failed dreams of money, reward, of exploitation of workers and land.
The mining towns of California, Oregon, Washington seemed to perfectly unite the twin Gothic places of wilderness and ruin. Bierce laid out "The Secret of Macarger's Gulch", weaving into his story allusions to the original American crime of Indian genocide and the connection to the lost Old World, setting out the West as the wilderness compared to the civilized East Coast. Writers like Morrow and Emma Frances Dawson wove in and out of supernatural and down-to-earth fiction, but keeping with the idea of the West as the frontier, the wilderness.
I don't think there's any doubt that New England Gothic remains the American Gothic to many people; even without Stephen King, we'd have Lovecraft and Hawthorne and the Salem witch trials. And there is something definitively Midwestern about Supernatural, to say nothing of the Children of the Corn. But the West Coast has a claim to the Gothic in the American mind in its own way, reminding us not just of the natural wilderness and the initial crimes of white America but the greed that drove expansion to the West--an insatiable greed that would always ultimately starve.
Further Reading:
Oh wow, an AskHistorians thread I can contribute to.
Among horror-themed classics that have entered canon, the vast majority of American literature is set in the east coast, usually setting itself in New England or, in, the case of Southern Gothics (such as Mark Twain), the Deep South.
The New England setting can trace itself from at least the 19th century from the likes of Nathaniel Hawthorne, Washington Irving, and Ambrose Bierce, but is a trend that follows through with 20th century authors like H.P. Lovecraft, Shirley Jackson, and of course Stephen King.
The oldest writing advice is to write what you know, however there's something to be said about the New England setting especially when compared to the Pacific Northwest. This setting is generally typified by: a foreboding environment and weather of dense forestry, fog, rain, and sparse or outright isolated towns and cities, early nights that lead to long periods of darkness, and insular or outright xenophobic communities.
Expectedly, this type of setting is also utilized frequently by English authors. The best phrase I’ve heard for the subject is from a literary newsletter discussing M.R. James and Angela Carter that coined the term “Sylvan Dread,” and which posited that the wilderness has and will prove to be a popular theme in horror literature not only because of the fear of the unknown--of beasts lurking in the darkness, but also of a fear of emptiness. “Nature, we're told, abhors a vacuum, and left to our own devices, we're all too ready to fill the empty places. If we're not at ease with the forest, perhaps it's because we're not at ease with ourselves. In the end, even the threat of emptiness will trigger its own fear. Even when the Indians are all gone, and the last wolf killed, the woods may still be a fearful place. What will we dream of then?”
This concept of Sylvan Dread easily translates into the Pacific Northwest, however the setting is virtually nonexistent in 20th century horror literature until around the 1970’s. Bigfoot, who has had alleged sightings since the 1800s, has only relatively recently been brought into popular culture. I believe that 1970’s Bigfoot was the first time he made an appearance on the silver screen, and after that he’s had a slew of B-rated grindhouse films to his hairy name (roughly half of which are set somewhere other than the Pacific Northwest).
Perhaps the most mainstream and successful attempt to move this setting out west was Stephen King’s The Shining, which is set in Colorado but clings to the ideas of isolation and wilderness mentioned above. Of course, Stanley Kubrick’s film version was also set in Colorado but was partially shot in Oregon and the Timberline Lodge still gets bookings purely because of The Shining. Notably, the film version of King’s Stand by Me would change the setting from Maine in the original novella to Oregon. Finally of note, though not strictly horror nor supernatural, both the book and film versions of One Flew Over the Cuckoo’s Nest are set in Oregon.
Likely the next solid, mainstream supernatural horror piece to feature the Pacific Northwest (and focus on the natural setting) would be Twin Peaks. The American remake of The Ring in 2002 also brings an interesting facet to this concept, as Seattle, Washington is used as a stand in to the original Ringu’s Tokyo (which itself is highly influenced by M.R. James’ ghost stories).
Tldr; Using the Pacific Northwest as a setting for the supernatural and horrible is an idea that has existed since the early roots of American literature but only been exploited, primarily in film and somewhat in literature, since roughly the 1970’s. However, the concept of vast, empty wilderness has been a trope in horror literature since the days of the Gothic Horror and Romantic movement.
Edit: Requested Sources and Further Reading:
M.R. James and Sylvan Dread by Steve Duffy from The Ghosts and Scholars M.R. James Newsletter
On the Supernatural in Poetry by Ann Radcliffe, which details and elucidates on (what I feel) is a necessary delineation between what is termed terror and horror in the Gothic genre (and subsequently the Horror genre). Duffy's writing on so-called Sylvan Dread expands on Radcliffe's thoughts on terror. H.P. Lovecraft also penned a similar essay titled Supernatural Horror in Literature.
Danse Macabre by Stephen King, though somewhat dated as it was published 1981, expands on Radcliffe's supposition of terror vs. horror (adding a third level of revulsion as well) and thoroughly explores the evolution from Gothic literature to speculative and pulp fiction, and eventually the crossing of the cluster of genres (horror, thriller, suspense) moving to screen.
Though admittedly I've only thumbed through it and not delved into it fully, Shock Value by Jason Zinoman is a well researched book that traces the expansion of the horror genre on film in the 1960's and 1970's.
Finally, for casual readers: TVtropes has a page referring at length to this thread's topic called Lovecraft Country.
To expand upon what others have said, but focusing more on the Pacific Northwest in television and film, Twin Peaks is widely seen as one of the more influential television shows of the last 30 years (e.g., in Alan Sepinwall's The Revolution Was Televised), with its episodic structure, cinematic feel and American Gothic themes. As a combination of these elements, Twin Peaks was widely seen as innovative in 1990. It was also a pop culture phenomenon at the time, with actors from the show on the cover of Rolling Stone and hosting Saturday Night Live, and merchandising tie-ins.
Given its nature as a pop culture phenomenon, shows which riffed upon elements of Twin Peaks - like Northern Exposure, The X-Files and American Gothic - unsurprisingly sprung up soon afterwards. Similarly, the current vogue for cinematic, episodic storytelling on television - Game Of Thrones and its competitors - can also clearly be traced back to Twin Peaks, via The Sopranos and Oz.
As a result, some of the more recent Pacific Northwest Gothic mentioned specifically here has deep roots in Twin Peaks - it's likely a reference point often used by television/film executives. Twilight's Bella, for example, pretty obviously echoes Twin Peaks' Laura Palmer in some ways: both are Pacific Northwest high school students dealing with supernatural horror while also unsure about how to choose between two male high school students.
In terms of Twin Peaks, the Northwest was always seen as crucial to the show. According to Reflections: The Oral History Of Twin Peaks, the original title for the show/pilot/standalone film written by David Lynch and Mark Frost that got turned into Twin Peaks was Northwest Passage.
David Lynch had spent some of his youth growing up in the state of Washington, and of course much of his oeuvre revolves around American Gothic in various forms. Similarly, lead actor Kyle Maclachlan was born and raised in Yakima, Washington, a couple of hours east of Seattle, while Sheryl Lee who played Laura Palmer was a local actress who got a part in the production, rather than a Hollywood transplant. In Reflections, more than one cast member identified the quite Gothic Pacific Northwest atmosphere as crucial to the success of the show - Michael Horse, for example, who played Deputy Tommy Hill, says in Reflections that "I have a lot of friends up in Washington and there's stuff out there in those forests. There's spirits that live up there", while Joan Chen who played Josie Packard mentioned the presence of Indian burial grounds.
Mark Frost's inspiration for the premise of Northwest Passage, according to the Reflections book, came from his family having a vacation home on a lake near Albany in New York; his grandmother had told him about a girl being murdered there. Nonetheless, Frost is also clearly well-read, with a deep interest in the occult - see this question about the theosophical beliefs referenced in Twin Peaks answered by /u/ancienthistory. Frost's recent tie-in book The Secret History Of Twin Peaks attempts to link Twin Peaks to much Pacific Northwest history, going as far back as the early explorations of Lewis and Clark in the Washington area, postulating that they encountered odd beings and situations (in a clear attempt to link the show to the deep Pacific Northwest roots of the American Gothic discussed by /u/sunagainstgold elsewhere in this thread).
In terms of the stated inspirations for Twin Peaks, Lynch and Frost mostly seem to have been transplanting other influences to the Pacific Northwest location Lynch grew up in. I don't see much about them riffing off previously established Northwest films; Lynch's cinematic influences include 1940s film noir and French arthouse film, and there are several references to these in the show, along with allusions to Hitchcock (Vertigo) and Kubrick (The Shining), and soap opera shows in the vein of Peyton Place.