To begin with, “You’ll Be Mine” is a Beatles’ song which is on their “Anthology 1” album. Since the song dates back to 1960, the name of the band at the time was The Quarrymen. Indeed, it was an experimental home demo from Paul McCartney’s old home, 20 Forthlin Road, Liverpool. Also of note is Stuart Sutcliffe on bass guitar. Obviously Ringo Starr was not one of The Beatles yet either.
Just to point out that “You’ll Be Mine” is the earliest Lennon-McCartney composition to have an official release. Although they released “That’ll Be The Day” which dates back to 1958, that was a cover song. So was “Three Cool Cats” etc. Therefore, this tune marks another milestone and so is historically important!
In Detail
Album
Recorded: Spring/summer 1960
Studio/Location: 20 Forthlin Road, Liverpool, home of Paul McCartney
Genre: Rhythm and blues, experimental
Track Duration: 1:38
Songwriters: Lennon-McCartney
Performers
Paul McCartney: lead vocal, also the guitar
John Lennon: backing and spoken vocals, as well as the guitar
George Harrison: guitar
Stuart Sutcliffe: bass

Anthology 1 Album (1995)
Track Source
You’ll Be Mine
Although they had the name of Quarrymen at this time, the individual Beatles all had a sense of humour. Indeed, that shows on this experimental track which is actually a parody of The Ink Spots. Sung in Paul McCartney’s bog (toilet) or bathroom at his family home, they used the room as their “acoustic chamber”.
What we get is a doo-wop recording where Paul McCartney sings in a deep baritone while John Lennon sings with shrill falsetto backing vocals on each last word sung by Paul. However John Lennon does come in half-way through with a mock-bass voice spoken piece.
The song sees Paul determined to make a woman his with John adding more weight to this. However, this early 1960 recording can be difficult to understand. This is because of the primitive recording equipment and the deep baritone voice which drowns the lyrics. The song ends with a crescendo of boisterousness and then laughter. But this is The Beatles in their infancy, a rare recording and well worth a listen.