Just googled that, and that's one of those answers to a wacky SBS question,
"R: Nice to meet you, Oda-sensei. I have a question. If One Piece was set in the real world, which countries would the nine Straw Hats come from? (Pen Name: MICHAEL JACKSONS' BROTHER)
O: Well. I'll just put what fits with the character's image.
Luffy: Brazil
Zoro: Japan
Nami: Sweden
Usopp: Africa
Sanji: France
Chopper: Canada
Robin: Russia
Franky: USA
Brook: Austria"
Now, call me crazy, but that answer is probably not canon. =P
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One Piece: Pirates with style!
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