This is what we found on Wikipedia regarding the All You Need Is Love:

"All You Need Is Love" is a song by the English rock band the Beatles that was released as a non-album single in July 1967, with "Baby, You're a Rich Man" as its B-side. It was written by John Lennon and credited to the Lennon–McCartney partnership. The song was Britain's contribution to Our World, the first live global television link, for which the band were shown performing it at EMI Studios in London on 25 June. The programme was broadcast via satellite and seen by an audience of over 400 million in 25 countries. Lennon's lyrics were deliberately simplistic, to allow for broad appeal to the show's international audience, and captured the utopian ideals associated with the Summer of Love. The single topped sales charts in Britain, the United States and many other countries, and became an anthem for the counterculture's embrace of flower power philosophy.

Our World coincided with the height of the Beatles' popularity and influence, following the release of their album Sgt. Pepper's Lonely Hearts Club Band. Rather than perform the song entirely live, the group played to a pre-recorded backing track. With an orchestral arrangement by George Martin, the song begins with a portion of the French national anthem "La Marseillaise" and ends with musical quotations from works such as Glenn Miller's "In the Mood", "Greensleeves", Bach's Invention No. 8 in F major, and the Beatles' 1963 hit "She Loves You". Adding to the broadcast's festive atmosphere, the studio was adorned with signs and streamers and filled with guests dressed in psychedelic attire, including members of the Rolling Stones, the Who and the Small Faces. Brian Epstein, the Beatles' manager, described the performance as the band's "finest" moment.

"All You Need Is Love", and its B-side, "Baby, You're a Rich Man", were later included on the US Magical Mystery Tour album and served as the two morals for the Beatles' 1968 animated film Yellow Submarine. Originally broadcast in black-and-white, the Our World performance was colourised for inclusion in the Beatles' 1995 Anthology documentary series. While the song remains synonymous with the 1967 Summer of Love ethos and provided the foundation for Lennon's legacy as a humanitarian, numerous critics found the message naïve in retrospect, particularly during the 1980s. Since 2009, Global Beatles Day, an international celebration of the Beatles' music and social message, takes place on 25 June each year in tribute to their Our World performance.