Impact of Geography
The Tokugawa Shogunate was located on the Japanese archipelago, or island chain, making it relatively disconnected from outside influences. Due to it's remoteness, Japan developed to have a moderately self sufficient rice based economy. Fish were common as well as rice because of the numerous habitats in the coastal seas created from warm and cool currents mixing. Because of this even when the outside world did make contact with Japan, trade was still not an absolute necessity, like it was for many other states. In this way, Japan's geography allowed the Tokugawa Shogunate to isolate themselves from the rest of the world, by refusing to trade, without suffering any immediate major consequences.