Deputy ruler of men out East (7)

I believe the answer is:

viceroy

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But I can't explain it at all! Could you help me understand?

(Other definitions for viceroy that I've seen before include "sovereign's governor" , "Ruler of a colony" , "Monarch's plenipotentiary - American butterfly, like (but smaller than) a monarch" , "Governor ruling in name of sovereign" , "One ruling in a colony" .)

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