Final answer:
From 600 C.E. to 1450 C.E., Japan was ruled by shoguns, who were military overlords. Samurai ruled their territories as independent kingdoms. The emperor ceded power to the shoguns, leading to a decentralized system.
Step-by-step explanation:
From 600 C.E. to 1450 C.E., Japan was ruled by a series of shoguns, who were military overlords. During this period, powerful samurai began to rule their territories as independent kingdoms. The shoguns commanded an army of samurai and held back invasions, maintaining a degree of separation from outside religions and cultures. In the late 1100s, the emperor ceded power to the shoguns, leading to a decentralized system with various local and regional leaders vying for political power.