"I had the Star Wars project in mind even before I started my last picture, American Graffiti, and as soon as I finished I began writing Star Wars in January 1973... In fact, I wrote four entirely different screenplays for Star Wars, searching for just the right ingredients, characters and storyline. It's always been what you might call a good idea in search of a story."
January 1, 1970
https://en.wikiquote.org/wiki/Star_Wars_(film)