Source 1: Beatle Biographer says Yoko Ono is Key To Split

Newspaper article published in the Spokesman Review on April 13, 1970.

The official biographer of the Beatles said Sunday the major cause of the breakup of the pop quartet appeared to be John Lennon’s marriage to Japanese artist Yoko Ono.

“If there was one single element in the split, I’d say it was the arrival of Yoko,” said Hunter Davies, author of “The Beatles, An Official Biography”

While he was writing the book, Davies was the most intimate confidant of the Beatles outside their own music and business organization.

Writing in the Sunday Times, Davies said that after Lennon and Yoko got together “the rest of the Beatles didn't matter any more.” … With Yoko, Lennon has mounted campaigns for world peace, held zany [wacky/crazy] art exhibitions, made radical movies, formed a wild rock and roll band and issued non-Beatle records. None of these activities included the other Beatles.

Source: http://news.google.com/newspapers?id=r8JWAAAAIBAJ&sjid=ZOsDAAAAIBAJ&dq=john%20lennon%20tal ks%20of%20beatles%20breakup&pg=5305%2C4336698

Source 2: John Lennon talks of Beatles’ breakup

Newspaper article published in The Dispatch, a North Carolina newspaper on April 25, 1971.

…. In discussing with host Tom Snyder the parting of the Beatles, Lennon says: “We broke up out of sheer boredom and boredom creates tension.”

He explains that the Beatles had known each other since they were teenagers and had grown too familiar with each other’s musical abilities. “We were together a long, long time. We just became stale.”

Source: http://news.google.com/newspapers?id=JeAbAAAAIBAJ&sjid=2lEEAAAAIBAJ&dq=john%20lennon%20talk s%20of%20beatles%20breakup&pg=5824%2C5027428

Source 3: Manager’s Death Started Breakup of Beatles

Newspaper article published in the Daily News, a Kentucky newspaper on January 1, 1971.

John Lennon says the Beatles started breaking up in 1967 with the death of their business manager Brian Epstein.

“That was the disintegration,” Lennon said in an interview in the jan. 21 issue of the Rolling Stone. … The four young men roared onto the world scene from a Liverpool basement club in 1962 but have been drifting apart recently. They have not appeared together in a public concert for more than two years.

Lennon said in the interview taped on Dec. 8 in New York City that McCartney “started taking over” after Epstein’s death. “We broke up then.”

“Paul has an impression—he has it now, like a parent—that we should be grateful for what he did for keeping the Beatles going. But when you look back on it objectively he kept it going for his own sake.

…I can’t speak for George, but I pretty damn well know we got fed up with being sidemen for Paul,” Lennon said.

Another source of conflict was Yoko Ono, Lennon’s Japanese-born wife. “They despised her,” he said. “They insulted her and still do.”

Source: http://news.google.com/newspapers?id=o60cAAAAIBAJ&sjid=gEYEAAAAIBAJ&dq=managers%20death%2 0started%20beatles%20break%20up&pg=5140%2C46265 SOURCE 4: Why Did The Beatles Break Up? McCartney Says Yoko Ono Wasn't Responsible

Newspaper article published in the International Business Times on October 31, 2012.

In a new interview Paul McCartney debunks the long-held belief that Yoko Ono, wife of John Lennon, was responsible for the breakup of the Beatles. McCartney not only absolves Ono from breaking up what might be considered the all-time greatest musical group, but also credits her with inspiring Lennon to try new things musically.

“She certainly didn’t break up the group,” McCartney told British journalist David Frost, according to the BBC. “I don’t think you can blame her for anything.”

…

“When Yoko came along part of her attraction was her avant-garde side, her view of things,” McCartney, now 70, said. “She showed him another way to be, which was very attractive to him. So it was time for John to leave.”

McCartney also said that Lennon wouldn’t have written “Imagine” without Ono’s influence and he would have “definitely” left the group regardless.

The rumors that Ono was responsible for the band’s break-up is a convenient scapegoat, but there was clear evidence the Beatles’ days were numbered. The Guardian reports McCartney admitted that Ono’s participation the group’s recording sessions was a point of frustration for him, a major point of contention [debate] among Beatles enthusiasts for decades.

The true dividing force in the Beatles’ latter years was new manager Allen Klein, who replaced the beloved Brian Epstein when he died in 1967. Klein came into the picture at a time when the Beatles egos were inflating [growing] as fast as their creative differences.

Source: http://www.ibtimes.com/why-did-beatles-break-mccartney-says-yoko-ono-wasnt-responsible-855824