Minamoto no Yoritomo
Minamoto no Yoritomo was a Japanese shogun, founder of the Kamakura shogunate. During the 12th century the local aristocracy in Japan became transformed into a professional military class (the bushi). Rivalry between the two most influential bushi clans, the Taira and Minamoto, was transmitted to the imperial court in Kyoto, as members of the military aristocracy were used by the court for military and police purposes.
In 1160 the Taira defeated and killed Yoshitomo Minamoto, head of the Minamoto clan, and imposed a dictatorship on the court. Yoshitomo's sons, Yoritomo and Yoshitsune, were spared death and sent into exile. In 1180 remnants of the Minamoto received a secret call from the court to rid the country of the Taira. Yoritomo succeeded in raising forces in eastern Japan (the Kanto) and under the leadership of several Minamoto generals, notably his half brother Yoshitsune, drove the Taira from Kyoto and ended their power at the Battle of Dan-no-ura in 1185.
Meanwhile Yoritomo consolidated his hold over the Kanto, enlisting all possible bushi as his retainers (gokenin) and confirming their land-holdings. He was granted successively the titles of military governor in chief (soshugo), general of the right imperial guard (ukonoe-taisho), and in 1192 barbarian-subduing generalissimo (sei-i-tai shogun). He established his headquarters (bakufu) at Kamakura and began to exercise increasing control over the country.
Yoritomo did not usurp authority from the imperial court but exercised delegated military and police functions. However, since he was able to appoint his retainers as provincial military governors (shugo) and land stewards (jito), he was in possession of a nationwide organization with far-reaching military and even civil powers. Yoritomo thus set the patterns of military rale which lasted until the mid-19th century and which by the 14th century left the emperor with only ritualistic functions. The two subsequent shogunal lines, the Ashikaga and Tokugawa, claimed descent from the Minamoto.