WHEN Johan Kugelberg’s godson started bingeing on early hip-hop in the midNineties, the erstwhile garage rock collector was intrigued. The records were primitive disco rap from the last gasp of the Seventies, as raw and homemade as the punk that was taking on allcomers in Britain at that time. Kugelberg was minded to check out a book or two, maybe a couple of compilations to fuel his interest. He checked. There was nothing.

“I couldn’t figure out where these records came from. There was so little available on the early days of what has become a pop culture behemoth. No CDs even, which meant I quickly became fascinated, and decided to document it as well. It felt very much like urban archaeology.”

The result of Kugelberg’s “fan boy detective work” is the Born in the Bronx exhibition at the Vinyl Factory gallery, Soho. It features the previously unseen photography of Joe Conzo, images that predate the iconic B-boy pictures of Jamal Shabazz, Martha Cooper and Henry Chalfant by several years. There are flyers and posters for hip-hop shows, and an exhibit of unreleased late Seventies “battle tapes” — live DJ recordings made years before rap even made it to vinyl.

This feels like the dawn of the modern world, when a new kind of music was being created with two turntables and a stack of top-secret samples; the point at which black urban culture began to sway white youth globally.

What jumps out is the sense of newness, of real excitement. The whole movement was born in the Bronx, “unbelievably humble surroundings,” says Kugelberg. The Bronx had been a stable, attractive area of middle and working-class homes until 1959 when an expressway was built through the centre of it, destroying communities and leaving the South Bronx — already the poorest area — as an isolated ghetto.

By the mid-Seventies urban blight was all over the Bronx — it was dangerous to walk the streets even in daylight. Gangs such as the Black Spades and the Savage Nomads fought turf wars. Yet within a culture that had an estimated 300 gangs with 20,000 members there was a chance to turn a negative into a positive.

Joe Conzo was born and raised in the South Bronx. “I was at school with DJ Tony Tone, a hip-hop pioneer. I was the school photographer. My dad was Tito Puente’s manager, so I’d already photographed salsa legends such as Ray Barretto — I wanted to document my culture. South Bronx is in my blood. A lot of good things are happening now, but back then it was famous for high crime and burnt-out buildings. In the Seventies people used to come over from Europe to make Second World War films in the South Bronx because it looked like Berlin in 1945.

“Anyway, Tony Tone asked me to take pictures of his group, the Cold Crush Brothers. I followed them to shows, it just blew up. They had such a following.”

This was around 1978 and 1979, with disco at its peak. But Conzo and his friends were too young to get in to clubs. “The venues were parks. Jams in the park, turntables and a microphone, that’s where it all started, all over the Bronx. You’d need a lamp-post, or a friendly store that would let you use their electricity. But that’s how people started making names for themselves: Afrika Bambaataa, Tony Tone, Grandmaster Flash . . .”

The result was Conzo’s unique collection of some 1,300 instinctive documentative photographs — there were shots of jams in Crotona Park, legends such as Kool Herc and the Treacherous Three, ex-gang members turned B-boys, DJs, and MCs: “I was just part of the youth trying to make a statement. It was my way of communicating with people. Plus, girls love to have their photo taken.”

There had been no visual record of the era until Kugelberg met Joe Conzo through a friend of a friend. Conzo had just come out of a decade of drug dependency, during which his family had hidden his negatives for safekeeping. He now works for the New York fire department, but has started to carry a camera with him once again. MTV, VH1 and the British magazine Hip- Hop Connection are keeping him busy.

“When I saw Joe’s pictures it blew my mind,” says Kugelberg. “He was starting to reinvestigate a portion of his past. Some rolls of film hadn’t even been developed. From nothing, there was suddenly a rich visual candy store of the early days of hip-hop.”

Navigating and accumulating over the past decade, Kugelberg got lucky when a friend of his went to look at a jazz collection: “He saw a shoebox full of flyers and ephemera, an incredible cache. That led me to to Buddy Esquire.”

With the disposable nature of flyers, it is incredible that not only has Kugelberg found so many, but that the paste-ups still exist, beautiful scissors-and-glue artefacts from an era just before computer fonts would render the style redundant. Esquire had been a graffiti artist since 1972. His first flyer was created for a jam in 1977. A year later he was doing two or three a week for around $10 a go, all with a style that echoed Art Deco cinema posters. They are a clear American counterpart to the xeroxed UK fanzine scene — Sniffin’ Glue, Ripped and Torn et al — that grew out of punk. They may not be polished in any way, but they possess an extraordinary power. Kugelberg’s “ultimate goal is for this collection to travel the world and end up in a New York-based institution. I’m talking to NYU. It’s in the works.”

Other artefacts on display include a 7in single of Yvette and the Kids’ Funky Drummer glued on to a Santana album. At first it seems puzzling, then it clicks: at the dawn of hip-hop there were no 12in singles, and have you tried scratching with a 7in? Bono and his precious hat should take note — this is a truly iconic object.