In a dimly lit sidestreet in London’s East End there is a black box of a building scrawled with graffiti. A CCTV camera perched above the door signals it probably isn’t a squat, but there is no signage. Inside, past three sets of doors and a changing room cordoned off with an old tarpaulin, is a shadowy warren of alcoves, cages and dark corners. Knee-high leather boots hang from iron chains looped through ceiling hooks like fetish bunting. Men kitted out in chaps and overcoats prowl the corridors, while others sip Foster’s, waiting for a nod and a wink. A gregarious barman greets regulars while hairy-chested musclemen appear on a small screen next to an ice bucket.

This is the Backstreet, London’s only remaining gay leather bar. But after a 33-year run serving London’s kinksters, its days might be numbered. “The developers have been sniffing around us for years,” says Aaron the barman. “They want to build another high-rise.” Opposition from Tower Hamlets council and community activists has granted the club a brief reprieve, according to the staff, who all work under the assumption that any day could be the venue’s last.

A string of closures has caused concern for those interested in a variety of fetishes, but the leather scene seems to have been hardest hit, particularly in London. Bars such as the Coleherne, the Anvil, Bloc, Substation and, most recently, the Hoist, have all disappeared into the annals of gay history, replaced with gastropubs, luxe apartments and identikit offices. Rising rents, competitor fetishes and competition from online dating apps have all been a turn of the screw. Aficionados fear its decline is another milestone in the gay scene’s slow descent into homogeneity.

“If some people want to have their matching knitwear and a cocker spaniel, then I’m happy for them,” says Nigel Whitfield, director of the Breeches and Leather Uniform Fanclub, “but some of us don’t. For lots of kinky people, we knew we were kinky before we knew we were gay. Losing these spaces is a tragedy.”

On today’s gay scene, leather denotes an aesthetic and, sometimes, a set of sexual practices. An entry-level leather fetish might just look like getting your rocks off in a well-cut bomber. But for the more committed, it’s a full look: boots, trousers or chaps, belts, shirts, jackets, overcoats, captain hats, all in premium, black leather. The sex tends towards BDSM, from rough horseplay to sadomasochism.

Facebook Twitter Pinterest The sex tends towards BDSM: aficionados in gear for Reading’s Pride Parade in 2017. Photograph: Geoffrey Swaine/Rex/Shutterstock

“For me, it’s all about the sensory experience,” says Eder, a 34-year-old leatherman who moved to London from Mexico nine years ago. “It’s the look, the feel, the smell – combine it with sex and it just feels amazing.” He discovered leather five years ago and estimates he has spent “a few thousand pounds” on the gear to date. Leather matters to Eder: he ended a long-term relationship because his ex was “vanilla” – a term for people not into kink or fetish – and has since explored his tastes more extensively on Recon, the world’s largest fetish app for gay men. “It doesn’t define me, but it makes me feel so much more confident,” he says. “It’s not just the sex, there’s a community, a social element that provides you with a sense of belonging.”

Eder’s story of stumbling upon leather online, exploring in real life, and discovering some form of community was common to the leathermen I spoke to, but it’s only the latest incarnation of a famed subculture that stretches back to the post-war boom of America’s coastal metropoles.

Leather as a gay subculture traces its roots back to the appearance of US biker gangs in the 1940s and 50s. Leathers were practical, but the rugged masculinity of biker culture imbued the material with an allure that spoke to men interested in men. Among gay men, leather was also a rejection of the tropes of effeminacy and passivity that homosexuality had accrued since the mid 19th century, a disavowal of the “sweater queens” – well-to-do, preppy gay men – of the time. “Leather was everything that the self-consciously effeminate homosexuals weren’t. They were some of the first gay men to reclaim masculinity,” says Eric Chaline, author and historian of gay sadomasochism.

International travel – at least for the wealthy – helped the US leather scene percolate across the Atlantic, notably to Amsterdam, Berlin and London.

In the UK, leather subcultures first seem to have taken root in London in the late 50s, though the history of those years has largely been lost. Networks of wealthy and closeted gay leather fans hosted invitation-only private parties to avoid the glare of the authorities.(Homosexuality for those over the age of 21 was not decriminalised in England and Wales until 1967, and some S&M practices remain illegal to this day.) The scene was necessarily limited to the middle classes: hosting orgies isn’t easy when you are crammed into a two-bed terrace with a wife and kids, and leather gear is rarely cheap.

Increased rents, police attention, the Aids crisis and prejudice have all had an impact on the gay leather scene. Photograph: Matt Spike

From the 70s onwards, fan clubs for leathermen popped up in London, Brighton, Manchester, Birmingham, Bournemouth and elsewhere under the guise of Motor Sport Clubs, disguising the gay fetish as a passion for biking. Around the same time, permanent venues rose to the fore. The Coleherne, a bohemian pub in Earl’s Court, became a lodestar for the leather scene. The horseshoe-shaped bar separated regular punters and a morass of leathermen. At the same time, Tom of Finland sketches of burly men in leathers and denim spread through nascent fetish communities pushing life to imitate art.

The gay leather scene had reached its peak. Thousands of leathermen congregated in multiple micro scenes across London, while thousands more revelled at club nights and events further afield.

Then came a crisis. In 1981, the New York Times reported a “rare cancer spotted in 40 homosexuals”. In San Francisco, one of the first Aids-related deaths was Tony Tavarossi, founder of the city’s first leather bar. Entire communities were eliminated. Bars closed. Hospitals swelled. The leathermen were some of the first to go.

Kellan Farshea, a veteran sadomasochist and campaigner for sexual liberty, recalls the early years of the crisis in the UK. “The Aids crisis was very much based in the leather community because that’s where a lot of the sex clubs were. A lot of the people involved in Earl’s Court were wiped out completely.”

But the virus wasn’t the only threat. “Every single leather S&M club in London was raided by the police at least once, but they couldn’t get any convictions because juries wouldn’t convict us,” says Farshea. The high-profile conviction of gay sadomasochists arrested in Manchester in 1987, known as the Spanner case, drew lurid headlines and stoked public prejudice. A campaign to appeal the conviction, spearheaded by Farshea and others, went through the high court and House of Lords before being referred to the European high court. The ruling on the case holds to this day and it is still not possible to legally consent to a range of “extreme” S&M practices.

Decades of stigma, epidemic and state persecution haven’t killed leather, but the feeling that the scene – or at least its physical spaces – is in decline is widespread.

“The internet changed everything,” says Farshea. Apps such as Grindr and Recon mean getting off doesn’t necessitate going to a club; online hookups don’t come with a £15 cover charge; and they are not limited to a venue’s opening hours.

But the internet has also fractured, and democratised, fetish. Retailers and club owners were often guided by their particular tastes – leather boots, in the case of the Backstreet’s owner – that dictated what people had to be into in order to get access to the kinds of sex they were chasing. “Leather was the dominant practice and discourse of gay BDSM from the 1950s to the 80s,” says Chaline. If you wanted to get tied up of a Saturday afternoon, chances are you had to do so in leather.

Facebook Twitter Pinterest A gay couple at an S&M Pride march in London, 1995. Photograph: Steve Eason/Getty Images

According to Farshea, leather’s hegemony in gay BDSM scenes was as much about its commercial saleability as some mysterious gravitation towards processed cow skin. When the full look can cost north of three grand, it’s perhaps not surprising that younger generations are opting for PVC or rubber, a scene that has “exploded” in the past 10 years according to Sandy Pianim, brand director at Recon. “The leather scene hasn’t modernised, it hasn’t evolved,” he says. Many leather nights still exclude women. Lesbian BDSM nights existed separate from the gay men’s scene, but no clubs have lasted. The scene also remains glaringly white, according to Pianim. And in a time when queer cultures are shifting to conversations around gender rather than sex, leather’s celebration of unfettered masculinity feels out of joint, he argues. “Leather is based on this archetype of hyper-masculinity that doesn’t resonate in the way that it once did. Our cultural archetypes have changed.”

For all the speculation on the reasons for the leather scene’s decline, however, there is a much more mundane truth. Venues in London that cater to specialist audiences, from leather fetishes to the queer communities more broadly, have been buffeted by spiralling costs, predatory developers and councils turning a quick buck to survive swingeing budget cuts. People in other cities in the UK, where venues were sparse due to the difficulty of maintaining premises catering to a much smaller scene, now rely on one-off nights or travelling to fetish events abroad.

For the leathermen who spoke to me, old-school bars can’t be replaced with Grindr-fuelled hookups or occasional events such as Folsom Europe, a continent-wide fetish and leather festival held annually in Berlin. Farshea fears the death of physical venues will make it harder for him to meet with fellow campaigners. Whitfield is concerned that the unique atmosphere of a leather bar will be lost to history. And Eder, who has accrued a “leather family” in his five years on the scene, fears that community bonds are weakened when that community has nowhere to meet.

“It’s always been the freaks who have been the canary in the coal mine,” says Whitfield, whether in the fight for basic rights or in the ongoing closures of minority spaces.

For now, the Backstreet lives on, throwing specialist parties for rubberists and occasional gigs to keep afloat. For how long, though, nobody quite knows.