All Japanese are Buddhists. This is a tricky one. Since a large majority of the Japanese population does partake in the many ceremonies that take place throughout the year in Japan. And most of them happen at Buddhist shrines or temples the fact remains that not to many Japanese people are active practicing Buddhists. Due to history and the societal norm of doing what everyone else does regardless if they agree with it or not a majority of Japanese do participate in Buddhist ceremonies but as far as being active practicing Buddhist. I am afraid that is nothing more than a myth.