Happy Bithday to John Lennon! He would have been 72 today. Listen to the Fab 4 at 4 and iHeartRadio Top 6 at 6 for a tribute to John Lennon!

The attendees of John's 31st Birthday Party sing "Happy Birthday":

Born and raised in Liverpool, Lennon became involved as a teenager in the skiffle craze; his first band, the Quarrymen, evolved into the Beatles in 1960. As the group disintegrated towards the end of the decade, Lennon embarked on a solo career that produced the critically acclaimed albums John Lennon/Plastic Ono Band and Imagine, and iconic songs such as "Give Peace a Chance" and "Imagine".

John tries to explain to Sean about how birthdays work and later explains the Sun:

After his marriage to Yoko Ono in 1969, he changed his name to John Ono Lennon. Lennon disengaged himself from the music business in 1975 to devote time to raising his infant son Sean, but re-emerged with Ono in 1980 with the new album Double Fantasy. He was murdered three weeks after its release.

Rare footage from John's 31st Birthday Party on October 9th, 1971 in a hotel room in Syracuse, New York with Ringo and Maureen Starr, Yoko Ono, Jim Keltner, Allan Ginsburg, Phil Spector, Klaus Voorman, and others:

Lennon revealed a rebellious nature and acerbic wit in his music, writing, drawings, on film and in interviews. Controversial through his political and peace activism, he moved to New York City in 1971, where his criticism of the Vietnam War resulted in a lengthy attempt by Richard Nixon's administration to deport him, while some of his songs were adopted as anthems by the anti-war movement.

Janis Joplin and the Full Tilt Boogie Band dedicate "Happy Trails" to John Lennon, circua 1970:

As of 2012 Lennon's solo album sales in the United States exceed 14 million units, and as writer, co-writer or performer, he is responsible for 25 number-one singles on the US Hot 100 chart. In 2002 a BBC poll on the 100 Greatest Britons voted him eighth, and in 2008, Rolling Stone ranked him the fifth-greatest singer of all-time. He was posthumously inducted into the Songwriters Hall of Fame in 1987 and into the Rock and Roll Hall of Fame in 1994.

Aerosmith's 70th Birthday Tribute to John Lennon:

Listen to John Lennon and The Beatles on iHeartRadio.