I was reading this interesting theory the other day , it was mentioning that in old chinese myth (i hope i remember correctly) there are
4 animals with their color regarding
4 seas
( N-S-W-E ) ! and it said that there are yellow monkey
(Kizaru) , red dog
(Akainu) , Blue bird
(Aokiji) and finally
WHITE DRAGON ! as each of them was from a sea , white dragon was from
east !!!
so with this assumption he believed that Dragon was an
admiral before , until something happened ( maybe he saw through the corruption in WG ) and he left marines to Build
Revolutionary Army !
I would try to find this theory for you , it was a really nice read !
EDIT : here is the link to the theory :
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