Minamoto no Yoritomo(1147-1199)
Founder of the first warrior government (bakufu) in Kamakura, and its first Sei'itai Shogun. Son of Yoshitomo and the daughter of Fujiwara Suenori. In 1158 at the age of twelve, he received his first court title and shortly afterwards he was appointed an administrator. At the end of that year, the Minamoto lost the Hogen War to the Taira forces, and young Yoritomo was sent to exile in Izu in the Kanto. Twenty years later, in 1180, a disgruntled prince Mochihito'o issued an imperial edict calling the Minamoto to rise against the Taira who were under the leadership of Taira no Kiyomori. Yoritomo, like a number of other Minamoto, used this edict to legitimize his call-to-arms against those associated with Taira no Kiyomori, or those who opposed Yoritomo. Although contemporary records (i.e., Azuma Kagami) describe Yoritomo's call-to-arms in terms of restoring the Minamoto clan and taking revenge against Kiyomori, it is more likely that Yoritomo's aim was primarily to establish semi-independency for warriors in the Eastern Provinces (Togoku). It was only in 1183 that Yoritomo sent his brother Yoshitsune and Minamoto Yoshinaka to destroy the Taira in the Western Provinces (saigoku)--and even that was the result of Taira assaults on him, not a pre planned strategy.
The war between Minamoto no Yoritomo's forces and Taira forces was a major civil war that continued for five years from 1180 to 1185, and is known as the Genpei War. In 1185, after Yoshitsune's brilliant sea battle at Dannoura, Yoritomo became the de-facto leader of a new warrior society. He established a military government that operated independently of the court, though in close co-operation, and was responsible for keeping law and order in the provinces. This was the beginning of a new chapter in Japanese history, dominated by a dual structure of rulership--by courtiers and warriors, each with its sphere of authority and power.
Minamoto no Yoritomo died in 1199, supposedly after suffering a serious illness. His eldest son Yori'ie succeeded him to become the second Kamakura shogun, and after his assassination Yoritomo's second son Sanetomo became the third Kamakura shogun. However, tragedies continued to haunt Yoritomo's lineage when his grandson (Yori'ie's son) assassinated Sanetomo (his uncle) because he believed that Sanetomo was behind the death of his father Yori'ie. After the assassination, the assassin was caught and executed, thus ending Yoritomo's direct lineage.