Why do Wales have a dragon on their flag?

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Tags

1. #welsh
2. #cathedral
3. #their
4. #recognised
5. #state
6. #supporter
7. #battle
8. #included
9. #carried
10. #dragon
11. #after
12. #signify
13. #tudor
14. #henry
15. #bosworth
16. #descent
17. #national
18. #officially
19. #royal
20. #which