The Kamakura Period in Japan

During the approximate one hundred years of the Kamakura period, Yoritomo set up a strong government and unified Japan starting in 1190 after conquering Fujiwara groups. This rule was strong until 1219. However, infighting in the family created the beginning of the end of the Yoritomo reign. In 1219, the control of the government changed from the Minamoto family to Yoshitoku, a Hojo figure, after the youngest son and heir to the throne of Yoritomo got assassinated. Yoshitoku ruled the government indirectly through Fujiwara leaders and never became the shogun officially. Yoritomo rule continued in appearance only (p.214).

In 1274, the Mongolians of the Yuan dynasty invaded Japan and fought on Tushima and Kyushu. They got defeated despite superior tactics and military supplies due to the strength of the Japanese resistance and their disadvantaged invader circumstances. Japanese resistance had been victorious and costly. Kublai decided to send another campaign in 1281 and land in the same places. Again, the Japanese more prepared resisted and gained a victory over the Mongolians. This had been costly for the Japanese especially in Kyushu and Tushima. The ruling government delayed in giving out any compensation to the Samurai that had fought in the battles and they became increasingly discontented over the inability of the government to acknowledge them or their contributions to Japanese freedom from Mongolian rule. This created an atmosphere in the nobility of disenchantment especially the families of Kyushu. Vassals became more disenchanted about the Kamakura rule as their control over outlying areas became decreased. Another problem that decreased the strength of the nobility over time had been the lack of the institution of primogeniture. This created a decrease in power for individual families as inheritances became smaller due to being divided amongst every male offspring. The men then had smaller land and financial holdings to start out until the upkeep of their status became too costly. Many men in the nobility class became poor over the generations as inheritances became smaller. The feudal system under the Kamakura had begun to unravel (pp.215-216).

In 1318, Go Daigo, a new emperor, had been crowned and sought greater power. He enlisted Monks from the area of Kyoto and military men to fight against the Kamakura in 1331 after the Kamakura tried to get him to abdicate. One of the Kamakura generals sent to recapture the emperor after he had been aided in escaping from the Kamakura decided to change sides and support the emperor instead. He then set up his own Shogunate in 1333 ending the Kamakura reign and starting the Ashikaga Shogunate in 1338. He did not unify Japan to the same extent that the Kamakura had. Yet, he did end their reign and start a new period for Japan (pp. 219-220).

The Kamakura period ended in 1333 due to several factors. They had an internal struggle that actually ended the Minamoto family line and decreased the power of the ruling family. The Mongolian invasions cost them economically and began the decline of their image of strength to their vassals in Japan. They became unable to rule over outlying areas and had a growing climate of disenchantment amongst the nobility. In this climate of disenchantment and decline of the Kamakura, the emperor decided to gain actual power for himself and recruited allies. This developed until the final battle between the Kamakura, the emperor and Ashikaga Takauji. Ashikaga, a general for the Kamakura, changed sides, became an ally to the emperor, defeated the Kamakura and gained power. He then named himself the new Shogunate in 1338. In conclusion, the Mongolian invaders, the lack of primogeniture, the emperor's interest in power and Ashikaga Takauji are the main factors that lead to the end of the Kamakura period.

References
Murphey, Rhoads. East Asia: A New History. 3rd edition. New York. Oxford University Press, 2003.