Why is Wales not in the UK flag?

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Tags

1. #first
2. #union
3. #meant
4. #could
5. #england
6. #created
7. #united
8. #dragon
9. #kingdom
10. #instead
11. #appear
12. #century
13. #wales
14. #because
15. #principality
16. #welsh
17. #included
18. #already