In 1974 music promoter Bill Graham had arranged for photographer Ken Regan to shoot Bob Dylan at the end of his tour with The Band for Time magazine. On consecutive nights, Regan spotted the same elderly woman in the crowd.

“She had a really interesting face but looked very out of place. She was about 40 years older than anyone else there. I just figured she was a music freak,” thought Regan. He mentioned her to Bill Graham, who explained that it was Bob Dylan’s mother, and that he should not take pictures of her. “I’d taken about four dozen!” the photographer revealed. “He told me not to release them because I’d never be let within 500 yards of Bob again.”

Later, he sent Dylan some shots from the concert, including those of his mother in the crowd. Regan’s note explained that he had not sent the pictures of Dylan’s mother to Time, but that he wanted him to have them. “There was no response from him at all, which really bummed me out,” said Regan.

Bob had given me free rein to shoot it all

A year later, during the summer of 1975, Regan was woken by the phone at 3am. On the line was Bill Graham’s partner, Barry Imhoff, who asked what he was up to for the next couple of months. “I could be anywhere. Why, what’s up?” came his response.

Imhoff was circumspect. There was talk of a tour, something a little different. He then passed the phone to Lou Kemp, a childhood friend of Dylan who ran Kemp Fisheries, who said he was co-promoting a tour, and they wanted Regan to go on the road with them to shoot it. Ken was incredulous. Dylan? Kemp Fisheries? He asked to get Imhoff back on the phone: “Barry, if this is a fucking joke, I’ll hunt you down and take you apart completely,” said the straight-talking, Bronx-born photographer.

Someone else came on the line, and Regan recognised the voice immediately – it was Bob Dylan. He apologised for waking Regan, and explained that he was in the frame as the photographer they were thinking of to document the tour. Dylan made a point of thanking him for the photos of his mother: by not releasing them, Regan had gained some trust.

Later that day, the photographer travelled to Manhattan, where Dylan was rehearsing. He explained that this was going to be a different kind of tour, with Joan Baez, Joni Mitchell, Ramblin’ Jack Elliott and T Bone Burnett on board already. Regan would be the only photographer with complete access – unrestricted and exclusive.

“Bob had given me free rein to shoot it all – on stage, off stage, dressing rooms, parties, trailers, whatever was going on,” said Regan. Later that day Regan was given the job: “We shook hands, and I never betrayed that trust.”

Regan went on to take almost 14,000 photos during his time with Bob Dylan’s Rolling Thunder Revue – and nine can be viewed in the gallery above.

Rolling Thunder: Photographs by Ken Regan includes 96 large-format pages. Just 750 individually numbered copies are being offered to collectors worldwide. Retail price on publication is £395 (Ormond Yard Press). Buy a copy here.