Julia was written by John Lennon for his mother, she died in a traffic accident in 1958. It is also the only solo Lennon recording in The Beatles’ song catalogue.
“The only solo Lennon recording in the Beatles’ catalog, “Julia” was the final addition to the White Album, recorded just three days before the album was sequenced. His original demo, recorded in May, had included harmonies from McCartney, but this version was just Lennon’s voice and guitar. “Julia was my mother,” Lennon said. “But it was sort of a combination of Yoko and my mother blended into one” — the “ocean child” in the lyrics refers to Ono’s name, which is Japanese for “child of the ocean.” To the end of his life, he often called Yoko “Mother.””
– Rolling Stone Magazine
They did 3 takes to perfect the guitar track, which was recorded onto four-track tape. The third track was the chosen one for “The Beatles” (aka “The White Album”)