Feudalism and it's system in Japan
Feudalism is a system that held Japan's structure together. This system contained of Shoguns, Samurais, Daiyamos, and Peasants. For example, in other systems one ruler controlled everything but in Japan everyone helped each other. Everyone also had to do their jobs or else the system would fail. Without this system their would be revolts and to much power, as well as Japan falling apart.
The warrior class
The samurai's had a very serious code that they must always follow. The samurai's also must wear several layers in battle and when not. They also must protect the shogun no matter what. They will learn how to protect by enduring intense training. This helped Japan because it gave them hard defense through highly disciplined warriors. With out the samurai the shogun and their people will die quickly. Japan would also lose some of it's most important history and be powerless.
Religion in japan is very important for all classes including the samurai. Japan's original belief was Shinto, formed in 500 B.C.E with over 3,000,000 followers. Buddhism (current belief) contains of two parts, Amida and Zen Buddhism. This helped with Japan's structure because it gave Japan a way into enlightenment. Without there religion their wouldn't be sacred rules, 8-fold path, ceremonies, Moral codes, and parts of daily life wouldn't be in Japan.