The yamato were a feudalistic group that lived in Japan. Feudalism is when a conqueror takes over an area and the people in that area pay tribute to the ruler. The Yamato had an emperor who was kept alive so that he could crown the leader of the gangs as the shogun which is the main general of the commanding army.  To make sure people paid their tribute the leader sent Vassals which were in charge of certain areas that would collect payment from the peasants.