Who was the 3 eyed Raven before bran?

Related questions

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2. Is Bran the 3 eyed raven?
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4. Why did they change actors for Daario?
5. Is Bran Stark the same actor?
6. Did Game of Thrones change actors?
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Tags

1. #tells
2. #rivers
3. #commander
4. #birth
5. #former
6. #beyond
7. #three
8. #targaryen
9. #theory
10. #bloodraven
11. #watch
12. #aegon
13. #night
14. #hence
15. #brynden
16. #names
17. #bastard
18. #legitimized