What was the main reason japan tended to isolate itself from china and korea? japan's beliefs–the people of japan's chosen religion was buddhism, which was very different from china's and korea's religious beliefs. japan's laws–japan's trade laws were very different from those in china and korea, so they preferred to trade between the islands rather than with other nations. japan's location–japan was a nation of many islands that were set apart from china and korea by the east sea (sea of japan). japan's relationships–japan did not have a positive relationship with china and korea because they tried to exert control over japan.