The battle of Brighton” screamed the Argus in the wake of the 1964 Whitsun weekend mod invasion that saw the town gripped by violent clashes between gangs of young men.

Like an Agincourt for Parka wearers, the seaside skirmishes of the 1960s have passed into mod mythology and find their legacy in the snappy boutiques, musical culture and tiger-tailed scooter processions of Brighton today.

For Ealing art school graduate Pete Townshend, son of a professional saxophonist father and singer mother, these mod jamborees were less about giving the rockers a good hiding and more about bringing like-minded young people (newly liberated from National Service) together in one place.

“My grandfather and grandmother performed on the pier long before I was born, but the family always kept a connection with the place,” the 62-year-old guitarist says of Brighton.

“When the mod thing started at the Aquarium [a popular gathering place] I went whenever I could. The mod gatherings in Brighton were the best I experienced. The violence was nothing to speak of. I can remember huge flocks of us running away from one rocker with a bike chain – we were really more concerned about saving our clothes!

“I have wonderful memories of sleeping under the pier with a bunch of mods and a girlfriend from art college, and going back to London on the Milk Train [the rail network that brought milk to large towns and cities].”

He says he’s visited many times since to “visit friends, to see the sea, to look at boats”.

“It’s a much more vigorous place now, more trendy I suppose, but I’ve always thought of Brighton as trendy.”

It was his experiences in the town as a younger man that would leave an indelible mark on Townshend, who had recently joined The Detours, an R and B outfit that also included schoolfriend John Entwistle and singer Roger Daltrey.

One iconic drummer and two name changes later, and The Who’s upward trajectory – propelled along by Townshend’s signature “windmill” and fondness for guitar destruction – brought them to the attention of the mod movement, which took the band to its collective heart.

As a writer, Townshend soon had some belters behind him in singles I Can’t Explain, Substitute and My Generation – perhaps the defining track of the 1960s – but a vaultingly ambitious streak pushed him in ever more progressive directions, resulting in concept album The Who Sell Out and rock opera Tommy.

He was to draw on his own past and the now distant clashes between mods and rockers for The Who’s 1973 record Quadrophenia. Set in London and Brighton as the mod cult was waning, it tells the story of Jimmy, a struggling teenage mod.

“The mod movement of the 1960s was almost forgotten at the time of the recording,” he says, adding he felt it needed to be rehabilitated in the public consciousness.

“Historically, the conflicts on the beaches are remembered, but only because they fit the language understood by the older generation of that time and its tabloid press. They were a small part of the mod happening.

“It coincided with the emergence of the first wave of great British pop, the Beatles onward, and it was a mirror to the music, an expression of the same need for validation and purpose, and the need to define our own new way of entertaining ourselves.”

Townshend’s love letter to mod was to become all the more powerful when the record formed the basis of Franc Roddam’s Quadrophenia feature film, which celebrates the 30th anniversary of its release this year.

With a cast including Phil Daniels in the lead role (Johnny Rotten, a friend of Townshend, had been considered), Toyah Willcox, Leslie Ash, Timothy Spall, Ray Winstone, Sting and Michael Elphick, the film would send yet another wave of people out to the local Vespa dealership. It’s still celebrated in the city today with regular screenings at the Duke Of York’s Picturehouse and last year’s convention, which reunited the cast at the Holiday Inn on the seafront.

For Townshend – who appointed Entwistle as musical director for the project and had little involvement in the story – the release of the film coincided with bleak times in his personal life.

“I was on a big drinking jag when the film was made. To achieve what I’d managed to achieve as a writer and performer in the years from 1964 to 1976 required full-time work from me. When the other band members were resting between tours, I was working, writing, or researching. I didn’t get a break.”

By the time the film was released in 1979, The Who had lost drummer Keith Moon to an overdose of a prescription drug to alleviate withdrawal symptoms from alcohol.

“The film passed me by in a bit of a haze, but when I came round from my stupor I was deeply impressed,” Townshend says.

Skip forward three decades and Townshend hopes this stage adaptation will breathe new life into his original vision. The musical – playing in a Brighton that has a star for The Who at the Brighton Marina Walk Of Fame – sees Townshend’s songs reworked in a bid to create “a new kind of musical”, more in keeping with the original rock opera concept.

Yet he admits that getting involved wasn’t an easy decision, citing “divided loyalties”; The Who have been keen to tour a concert version for some time.

“It took a big leap of faith for me to say no to my beloved mate Roger and yes to the huge ménage of reprobates who are now putting on the show. I think in the end my aspirations as a composer and writer for the theatre proved more powerful than my desire to play this wonderful music on stage with The Who.”

Differences between Townshend and Daltry are hardly anything new in a band that has had more than its share of bitter exchanges and punch-ups, but at the core of The Who is a friendship between these most magnetic of performers. And the “circus family” of a touring machine isn’t ready to grind to a halt just yet.

“I feel rather old all of a sudden, to be honest. I am very fit, but the aches and pains don’t go away after a tour the way they used to. That said, I will never make the mistake I did in 1981 when I declared I was leaving The Who. Roger simply wants me never to say never. I can live with that.”

Before The Who head out on the road for another hurrah, Townshend must oversee this new tour of Quadrophenia.

“What’s important is that the album, film and this musical all leave space for the audience to connect with their own internal story – in essence, that’s what the mod movement did – it gathered legions of people together, and they all looked the same, and yet the individual was exalted, invented.

“It has been called the beginning of the cult of the individual.In fact, it was the beginning of the freedom from militaristic subordination. We created our own army.”

* Quadrophenia will be at Theatre Royal Brighton, New Road, from Tuesday until Saturday, September 5. Call the box office on 0844 8717 650.