[quote=Heyitsjiwon]Korea is a bit too minor to really have any influence in this RP.
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Depends on China and Japan, really. We're right before the Meiji Restoration, so if you followed the same path, you could conceivably turn Korea into a regional power and intervene in, say, the Boxer Rebellion, as well as lay claim to some Pacific islands.

Sweden or Spain also work too. Sweden because you can conceivably unify Scandinavia if something bad happens to Denmark and Spain because. well, it's Spain.