Why did the Star Wars series start at 4?

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Tags

1. #numerical
2. #system
3. #plans
4. #later
5. #lucas
6. #because
7. #prequel
8. #strikes
9. #started
10. #episode
11. #renamed
12. #called
13. #while
14. #empire
15. #crawl
16. #trilogy
17. #however