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One Piece has it all; a great cast of characters with insanely creative (devil) powers, an exciting environment with a whole world to discover and a story that is so intriguing, and at times touching, that once you begin reading, you can't put it aside.
One of the things I really like about One Piece is how, occasionally, it feels very familiar on a level that's hard to understand. That is, until you realize how many references it has to the culture us Western fans grew up with - a fact surprisingly many fans whom I spoke to seem completely unaware of.
Most notably there are many references and pointers to fairy tales, particularly the ones collected and written down by the Grimm Brothers. To start off with a rather obscure and less well-known one, we have the tale of 'The Singing Bone' - I don't think I need to say any more, you all know who's meant.
We have a reference to Rapunzel (which yes, I know is heavily influenced by the Persian tale of Rudāba) in Shirahoshi, who has also been locked away in a tower by her father. There are subtle hints at Snow White on two instances as well - one, Alvida's line in the beginning of the series, going 'Who's the most beautiful on all the seas', not unlike Snow White's step-mother asking her mirror the same question. The other one is Doc Q giving away poisoned apples on Jaya.
There are references to Little Red Riding Hood during the Enies Lobby arc; when Jabra (the Wolf Zoan member of the CP9) attempts to lie to Sanji (who introduced himself as 'The Hunter') about being Nico Robin's brother he is shown in his half-wolf form with Robin in a red-hooded cloak. Finally, there are also several instances where Oda mentions the Town Musicians of Bremen, including the cover of chapter 34 and a color spread in chapter 604.
There are references to other, non-Grimm fairy tales as well, for example Jack and the Beanstalk in the Skypiea Arc, or Pinocchio (Usopp) but also a bunch of biblical stories, like Noah's Ark (even named 'Noah' in the series) or the story of Jonah who supposedly lived in a whale (he'd have certainly had space in Laboon - a real whale, not so much...).
Other allusions to Western culture, media or even locations include Jurassic Park (Little Garden Arc), Rudolph the Red-Nosed Reindeer and the Abominable Snowman (both Chopper), Santa Claus (Dr Kureha coming down from the mountain on a sleigh), Venice (anyone who's been there can confirm that Water Seven is based on it), Captain Hook (Crocodile), Zorro (Zoro), Melville's novel Moby Dick (the name of Whitebeard's ship) and probably many more.
Those are all the ones I could think of. Can you think of any more? Did you notice them while reading or watching the anime? Most of them are pretty straight-forward, but Oda manages to give them such a twist that they can be easy to miss. And what I've been thinking most about while writing up the above - which references are yet to come? Which famous fairy tales are left?
Update: Wow, some of the comparisons you guys brought up are pretty cool. Especially Eric Ester Burgos, big shout out to you man, I really enjoyed your post and everyone interested in cultural references should definitely click his name and go read it.