The Kamakura shogunate (鎌倉幕府) was a feudal military dictatorship ruled by the shoguns of the Minamoto family from 1185 to 1333 AD. Based in Kamakura, Japan, this period draws its name from the capital and is known as the Kamakura period.
Before the establishment of the Kamakura bakufu, civil power in Japan was primarily held by the ruling Emperors and their regents. Military affairs were handled under the auspices of the civil government. However, after defeating the Taira clan in the Genpei War, Minamoto no Yoritomo seized power in 1185 and became the dictator and the de facto ruler of the country. He asserted the primacy of the military side of the government and was given the title of shogun in 1192 while the system of government he established became formalized as the bakufu. The Japanese provinces became semi-autonomous under the daimyo, although in theory they were still obligated to the central government through their allegiance to the shogun.
After Yoritomo's death, his widow Hojo Masako essentially usurped the real ruling power from his Minamoto clan to her own Hojo clan. The Minamoto remained the titular shoguns, with the Hojo holding the real power - thus ruling through a puppet shogun and a titular emperor. The Emperor attempted to reverse the situation in a 1221 rebellion (called jokyu incident), but failed to wrest power away from the shogunate. A second attempt was made by the Imperial court in 1331, and was much more successful, particularly as the Kamakura's most powerful general, Ashikaga Takauji, chose to side with the Emperor. The Kamakura bakufu came to an end in 1333 with the defeat and destruction of the Hojo clan. This triumph was, however, short-lived, as Ashikaga Takauji promptly assumed the position of shogun himself, establishing the Ashikaga shogunate.