Fifty years ago today, on September 9, 1971, the late John Lennon released his classic second solo album, Imagine, which featured his enduring peace anthem of the same name.

Imagine was Lennon's first solo effort to top the Billboard 200 chart, and it's gone on to sell more than 2 million copies in the U.S.

Imagine's centerpiece, of course, was the title track, which was the only single released from the album. It peaked at #3 on the Billboard Hot 100. "Imagine" includes lyrics urging people to envision a peaceful world without possessions, without countries that separate us and without religion. Before his death in 1980, Lennon credited his wife, Yoko Ono, with much of song's lyrical ideas and content.

Other memorable songs featured on the album include "Jealous Guy," "Gimme Some Truth," "How Do You Sleep?" and "Oh Yoko!" Lennon wrote "How Do You Sleep?" as a vitriolic response to Paul McCartney's then-recent musical and media digs at John and Yoko.

Among the well-known musicians who contributed to Imagine were George Harrison; lauded session keyboardist Nicky Hopkins; bassist Klaus Voormann; drummers Alan White, Jim Keltner and Jim Gordon; and Badfinger members Tom Evans and Joey Molland. Lennon and Ono co-produced the record with Phil Spector.

Of course, hundreds of artists have recorded and performed "Imagine" over the years. Just a few examples: The song was performed as part of the closing ceremony of the 2012 Summer Olympics in London, and at the opening ceremonies of the 2018 Winter Olympics in South Korea, and this year's 2020 Summer Olympics in Tokyo.

Visit JohnLennon.com to find out about the various events planned to commemorate the anniversary.

Meanwhile, in the lead-up to the milestone anniversary, a few famous artists discussed their admiration for Imagine and its title track:

John Fogerty: "[Lennon] stated a philosophy in 'Imagine' that's one of those wonderful times where…it's a really great song, but it's also got a really great message, you know...The concept of having no borders and everybody is one and that there are many dreamers. And just a completely compelling melody…Yeah, that was a wonderful record, certainly."

Heart's Ann Wilson: "'Imagine' [turned] out to be one of the most beloved standards of our culture…I mean, it's just been done and redone and believed in. What an amazing mantra. And actually, it turns out that…those were Yoko's words…I think that song probably was the real fruit of [John and Yoko's] union, creatively."

Heart's Nancy Wilson: "The Imagine album was so intimate, more intimate than any Beatles album…would have been able to be, 'cause you would have had a George song, and maybe Ringo song, and Paul and John trading and…doing their Paul and John thing together. But, I think John…was going through a catharsis, like as a human, having been let out of the Beatle pen…and being able to do his own thing with the new love of his life."

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