Japan Journal 3
Isolation affected the economy by forcing the Japanese to use only currency they had available on the island- rice. Rice was the main form of currency in Edo Japan and a main part of the diet. They traded rice and the landowners who had land that could produce the most rice had the most power. However, rice crops could be wiped out by Tsunamis and storms. This meant that until the rice grew back, the landowners would have a low amount of money and food.
Isolation affected the social structure by making a the social structure clearly defined. You knew if you were at the bottom and who was at the top, and if you were an Outcast you knew that you were apart from everyone else. The social structure was sorted by importance. The Peasants were higher than the Merchants and Artisans because Peasants produced food, and currency. However the Daimyo were higher than the Peasants because they owned the land that produced rice. Isolation meant that they had to be self-sufficient and produce everything for themselves, so the people that produced necessary goods were higher in the social structure.
In Edo Japan the Emperor was in control, but Leyasu held all the power. The Emperor made him a Shogun. He made a bunch of rules to keep control of the Daimyo, like alternate attendance. He gave certain Daimyo he trusted domains next to Daimyo he didn't trust. The shogunate established rules about the Daimyo's dress and marriage. Isolation would have made it easier to maintain control because, the people couldn't leave Japan, people couldn't come in, and foreign objects were banned. If people couldn't leave they had to remain in Japan under the control of the Shogun.