who is the developer of this game?
Tetsuya Nomura is the director and Hashimoto the producer
Kingdom Hearts
 Development began in February 2000 with Nomura as director and Hashimoto as producer.
where did the idea for kingdom hearts come from The initial idea began with a discussion between Shinji Hashimoto and Hironobu Sakaguchi about "Super Mario 64" is 'kingdom hearts' a video game? Yes, a crossover between Square Enix and Disney based in a fictional universe
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Kingdom Hearts [SEP] History
To bridge the gap between the two games, "Kingdom Hearts: Chain of Memories" was developed. Nomura was hesitant about releasing a game on the Game Boy Advance because he felt the 3D graphics of the original game would not translate well into 2D. He changed his position after hearing that children wanted to play "Kingdom Hearts" on the handheld system.