Harrison Ford first got the part because he just happened to be on the set (as a carpenter) and the actor playing Han was missing during rehearsal, so Lucas had did read the lines to fill in - and liked him so much he replaced the other. So Ford took the job as his big break.
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Really? I thought it was because Harrison Ford was in American Graffiti. Mark Hamill auditioned for American Graffiti, but wasn’t in it.
Ford was in GRAFITTI and on friendly terms with Lucas. Right place, right time.