Why was Danzig a free city?

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Tags

1. #reichsgau
2. #polish
3. #sized
4. #invasion
5. #access
6. #danzig
7. #poland
8. #formed
9. #seaport
10. #other
11. #newly
12. #population
13. #german
14. #order
15. #nazis
16. #incorporated
17. #created
18. #after
19. #abolished
20. #prussia