The Beatles didn't seem capable of letting one of their final singles be.

They recorded multiple versions of "Let It Be" in late January 1969 at Twickenham Studios for use in a documentary film also called Let It Be. They then re-recorded Paul McCartney's song on Jan. 31 at Apple Studios in an attempt to get a final take.

George Harrison added a guitar solo, recorded through a rotating Leslie speaker, on April 30, 1969, and that version ended up pressed for release as a George Martin-produced single on March 6 – of the following year. By 1970, McCartney had returned to add still more elements to the song (while also recording over an original turn on bass by John Lennon), and Harrison added an entirely different solo.

Really, the whole project took a long and winding road. Engineer Glyn Johns produced a pair of Let It Be album acetates with different sequencing for the Beatles to decide upon. Both were rejected. By early 1970, Lennon had given the tapes to second producer Phil Spector, who'd recently produced Lennon's "Instant Karma" single. That was just weeks before the accompanying Let It Be film was set to premiere.

The title track included on the Let It Be album ended up with still more contributions from Spector. "About 18 months later, after the band had split up, John decided he was going to take the tapes and give them to Phil Spector and make an album for the tapes that I had recorded – which was basically all rehearsal tapes," Johns later told Yahoo! "Phil Spector turned it into this sugary, syrupy piece of shit with strings and choirs all over it."

Johns admitted to Rolling Stone that he preferred his own more bare-bones mix of the song, before "Spector puked all over it." In the end, Spector seemed to know what he was up against: "If it's shitty, I'm going to get blamed for it," he noted. "If it's a success, it's the Beatles."

Appropriately enough, "Let It Be" was the last track recorded for the project. Inspired by Aretha Franklin, McCartney began writing the song at the end of the album sessions. Late into January 1969, he still lacked a third verse. The full-group version of "Let It Be" taped on Jan. 31 was the last take on the last day of sessions at Apple. By then, the Beatles had ran through more than 300 different songs – not including unformed jams.

"Let It Be" was also the final song released by the Beatles before their dissolution was made official. The next single from their final-released album, "The Long and Winding Road," arrived two months later.

Listen to the Single Mix of the Beatles' 'Let It Be'

From the first, "Let It Be" was misunderstood as a religious statement, given McCartney's early reference to "Mother Mary." But he was alluding to his own mom rather than the virgin mother of Christian tradition. Mary McCartney died when Paul was just a teen, and he would often sense her comforting presence during moments of crisis.

These painful childhood memories led McCartney to focus more intently on music; they also provided a foundation for his friendship with Lennon, who lost his own mother in a traffic accident. "That became a very big bond between John and me," McCartney said in the Beatles' Anthology documentary. "We both had this emotional turmoil which we had to deal with, and, being teenagers, we had to deal with it very quickly."

With everything else that was going on, McCartney admitted to leaning on drugs as an emotional crutch.

"I was going through a really difficult time around the autumn of 1968," McCartney recalled in Marlo Thomas' book The Right Words at the Right Time. "It was late in the Beatles' career and we had begun making a new album, a follow-up to the White Album. As a group, we were starting to have problems. I think I was sensing the Beatles were breaking up, so I was staying up late at night, drinking, doing drugs, clubbing, the way a lot of people were at the time. I was really living and playing hard."

At this point, McCartney's mother, a victim of breast cancer, had been dead for 10 years.

"It was so great to see her because that's a wonderful thing about dreams: You actually are reunited with that person for a second," McCartney told Barry Miles in Many Years From Now. "There they are and you appear to both be physically together again. It was so wonderful for me, and she was very reassuring. In the dream she said, 'It'll be all right.' I’m not sure if she used the words 'let it be,' but that was the gist of her advice. It was, 'Don’t worry too much, it will turn out okay.' ... So, that got me writing the song 'Let It Be.' I literally started off 'Mother Mary,' which was her name, 'when I find myself in times of trouble,' which I certainly found myself in."

This was undoubtedly one of those moments, with McCartney's band falling apart.

"I think people were overdoing the use of substances - we certainly were," McCartney told the Salt Lake Tribune in 2011. "It was kind of common. It was the fashion – and anyone who remembers that time will know that. And I think I was getting, like, a little bit over the top with the whole thing – getting pretty tired and pretty wasted. And I went to bed one night and had a kind of restless night."

"Let It Be" became a double-platinum selling U.S. chart topper, helping its parent album to the No. 1 spot both in the U.S. and the U.K. McCartney eventually came to terms with the song's pious interpretations, despite its deeply personal meaning.

"Mother Mary makes it a quasi-religious thing, so you can take it that way, I don’t mind," McCartney told Miles. "I'm quite happy if people want to use it to shore up their faith. I have no problem with that. I think it's a great thing to have faith of any sort, particularly in the world we live in."

The single version of "Let It Be" also included the only known contributions by Linda McCartney in a Beatles song; she sang backing vocals. McCartney later formed Wings, his post-Beatles band, with Linda and Denny Laine from the Moody Blues.

 

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