This Friday, John Lennon would have celebrated a major milestone: his 75th birthday. In honor of that day, take a look back at how Lennon grew from a young boy into a superstar and eventually a peace activist. As TIME's Jay Cocks wrote after Lennon's death in 1980, the experiences of his youth would stay with Lennon throughout his musical career:
John Lennon grew up on Penny Lane, and after a time he moved to a house outside Liverpool , hard by a boys' reformatory. There was another house in the neighborhood where John and his pals would go to a party and sell lemonade bottles for a penny. The house was called Strawberry Fields. His boyhood was neither as roughly working-class as early Beatles P.R. indicated, nor quite as benign as the magical association of those place names might suggest. But John's adolescence in the suburbs, the garden outside the back door and the warm ministrations of his Auntie Mimi did not diminish either the pain or the sense of separateness that was already stirring.
His father, a seaman named Alfred, left home shortly after John was born, and his mother Julia sent him to her sister Mimi because, it was said, she could not support her child. John was 4 1/2 when he was farmed out to the suburbs. All the sorrow, rage and confusion of this early boyhood were taken up again and again in songs like Julia and Mother. These early years were not an unhealed wound for Lennon, but more nearly a root, a deep psychic wellspring from which he could draw reserves of hard truth.
Read more from 1980, here in the TIME Vault: When the Music Died