When the Beatles gathered at London’s Abbey Road studios in the summer of 1968 to record what became universally known as their White Album, John Lennon was consumed by a new firebrand song called Revolution, lying on their floor at one stage to distort his voice as he sang.

Paul McCartney, meanwhile, was singing pop songs about home-building Desmond and Molly Jones on Ob-La-Di, Ob-La-Da and a cowboy on Rocky Raccoon.

Forty years on, however, and it is McCartney who says he was the one who introduced the Beatles to politics.

McCartney, 66, paints a new picture of himself this week, in an interview with an intellectual journal, as a political animal. He claims it was he who converted Lennon to opposing the Vietnam war.

His critics see it as another piece of revisionism with McCartney seeking to alter people’s perceptions of what really went on in the Beatles.

He says he held a meeting with Bertrand Russell, the philosopher and pacifist, in London in the mid-1960s, which first alerted the band to the horrors of the Vietnam war.

“We sort of stumbled into things,” McCartney tells Prospect magazine. “For instance, Vietnam. Just when we were getting to be well known, someone said to me: ‘Bertrand Russell is living not far from here in Chelsea, why don’t you go and see him?’ and so I just took a taxi down there and knocked on the door.”

He adds: “He was fabulous. He told me about the Vietnam war — most of us didn’t know about it, it wasn’t yet in the papers — and also that it was a very bad war.

“I remember going back to the studio either that evening or the next day and telling the guys, particularly John [Lennon], about this meeting and saying what a bad war this was.”

McCartney says the band ignored requests from their publicist not to mention Vietnam when they went to America.

“Of course, we talked about it the whole time and said it was a very bad war. Obviously we backed the peace movement.”

If it was McCartney who politicised the Beatles, it was Lennon who voiced the opinions in song. He vented his feelings in Revolution. “You say you want a revolution,” he sang. “Well, you know, we all want to change the world.”

Later Lennon recorded more anti-war songs such as Give Peace a Chance. It was not until the start of McCartney’s solo career that he released his first protest song, Give Ireland Back to the Irish.

Jonathan Power, a school friend from their days together at the Liverpool Institute High School for Boys, is McCartney’s interviewer for Prospect. He tells the singer: “You were a megaphone for a generation.”

McCartney replies: “People often say to me, ‘Do you think music can change the world?’ and I do, on a lot of levels, and one of those levels is just the fact that famous musicians are listened to.”

He adds: “Perhaps in terms of responsibility we did sow some seeds for people who came after. People like [Bob] Geldof, Bono, people who have the megaphone now.”

McCartney’s recollections of the 1960s are at odds with those of some Beatles experts.

Alan Clayson, who has written separate biographies of all four Beatles, said: “I think Sir Paul is rewriting history, now that Lennon is gone.”

Spencer Leigh, who has just written a history of the Cavern Club with a foreword by McCartney, said: “Both Paul and John were interested in what was going on around them, but as to whether Paul politicised John I’m not so sure.”

Tariq Ali, who was one of the leaders of the anti-war movement in Britain, said yesterday: “It is not my recollection at all. It is possible McCartney met Bertrand Russell, but certainly I had no contact with Paul.

“When I asked Lennon why Mick Jagger came on our big anti-Vietnam war marches and he never did, he said he always regretted it, but Brian Epstein [the Beatles’ manager] told him that if he went on the marches he would not get a visa to go to America. If McCartney had been that way inclined we would have known.”

Hunter Davies, who spent 18 months with the Beatles during 1967-8 before writing their authorised biography, said: “At that stage the Beatles were open to all the smart, intellectual and artistic people trying to get them involved in things.

“It wasn’t just John. Paul was as interested in meeting these people and hearing their stuff.”

The interview with McCartney appears in the January issue of Prospect, on sale from Wednesday

PACIFIST WITH A STRING OF LOVERS

Bertrand Russell was a Nobel prize-winning philosopher, mathematician and social critic who proved to be one of the most influential British voices of the 20th century.

Born in Monmouthshire in 1872, he led the movement known as the “revolt against idealism”, which came to shape the study of logic, mathematics, linguistics and analytic philosophy.

Imprisoned for pacifism during the first world war, Russell spoke out against the rise of Adolf Hitler, imperialism, nuclear weapons, the advent of Soviet power and the Vietnam war.

Married four times and thrice divorced, Russell also indulged in numerous — even simultaneous — affairs with a string of lovers including Lady Ottoline Morrell, the actress Lady Constance Malleson and, it was claimed, Vivien Eliot, wife of the poet T S Eliot.

Politically active until his death at 97, he condemned Israeli aggression two days before he died.

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