I believe Yamato along with Harlock had a huge impact in Japanese anime, the stories set in space at the time were amazing. Akira's animation and use of color also knocked the hell out of everything at the time. Of course I'm going to go with Miyazaki's direction, and anything written by Osamu Tezuka. American cartoons specially Disney have influenced numerous artist in anime and video games. Everyone brings up Big O because it was a bigger hit here than in Japan, and because it was a huge hit here, CN put money up front for an extra 13 episodes and the second season, regardless of if it sucked or not. A great example of how Americans influence anime is Barefoot Gen, no Americans, no bomb, no movie. Seriously Americans due influence more anime than most people give credit for. If you think that Cowboy Bebop was not influence by American pop culture, you are fucking kidding yourself.
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