Stuart Sutcliffe met fellow art student John Lennon at the age of 19 at the Liverpool Art Institute. The two soon became best friends and for a time they shared a cramped apartment together, where Stu slept on a mattress on the floor. Their flat is vividly described by Cynthia Lennon, John's then-steady girlfriend: "Stuart's part of the flat consisted of one enormous room, totally devoid of any home comforts. A double mattress lay desolately in one corner of the room underneath a large, dirty window, bare of anything remotely resembling a curtain. The floor-boards were spotted with different coloured oil paint; an easel was in evidence which seemed to dominate the room; canvasses finished or abandoned in a fit of artistic frustration were scattered around without semblance of order. Stuart's flat was the archetype of a poverty-stricken artist's studio."
John and Stu were very close friends, and John shared the passion for art Stu did. John wanted very much for Stu to share his passion for music, and he invited him to be in his band, nevermind the fact that he couldn't play anything. When Stu sold one of his paintings in 1995 for £65, an unheard of amount for a studen't work in those days, John convinced him to spend it all on a Hoffner President 500/5 bass guitar. Stu tried very hard to learn to play, but to no avail. He was an artist, not a musician. An at first friendly but later mean rivalry between he and Paul McCartney soon developed, as Paul felt the band needed a good bassist. But John had his way, and Stu remained in the band. At gigs Stu was forced to play with his back to the audience so they couldn't see his fumbling fingers.
Before their first big gig, a two week tour in Scotland backing Johnny Gentle, the boys still didn't have a steady name for the band. Stu jokingly suggested "Beetles" as a play on Buddy Holly's Crickets. John then came up with the idea to spell "Beetles" with an "a" so the name would mean two things. They would be the "Silver Beatles" for a while before finally switching to just "Beatles".
The Silver Beatles were soon off to Hamburg, and it was here where Stu met Klaus Voorman. Stu and Klaus' girlfriend, Astrid Kirchherr, soon fell deeply in love. Astrid spoke only German, but this was no matter to Stu or herself; they were in love. She soon started learning English, and he German, and the two would later marry.
Astrid put Stu through many changes. She clothed him in leather, which the other Beatles later adopted, as well as gave Stu the first of the infamous "Beatle haircuts". When the others first saw it, they laughed in Stu's face, but soon they would all, save Pete Best, acquire the same cut.
While on their second Hamburg trip, Stu started to study art again at the Hamburg State Art College, where Astrid had studied. He gradually started distancing himself from the band, and when the tour ended and the rest of the Beatles went back to Liverpool in 1961, Stu stayed in Hamburg with Astrid.
One day Stu accidentally fell down the steps from his attic studio at Astrid's house. (This is confirmed by both Astrid's mother and Stuart's mum.)* Ever since this accident, Stu continued suffering massive headaches, which were becoming more and more frequent. On April 10, 1962, the day before the Beatles were to begin their third Hambury tour, Stu died from a brain hemmorrhage. The news devestated John, and he would always feel guilty for his death. He felt that if he had not pressured Stu into being in the band, the fight in Liverpool would have never happened and Stu would not have died. (Or, as in the second version of this story, John felt guilty because he believed he had caused the hemmorrhage to occur from the beating he gave Stu.)
* Many thanks to Bill Harry for this information. Please check his postings in the Beatles section on the Mersey Beat site.