Adoption of System and Taika Reforms Summary

  • Last updated on November 11, 2022

After the assassination of the leaders of the Soga family, Imperial Prince Naka no Ōe and his supporters proceeded to enact a series of reforms that attempted to bring Chinese institutional innovations to the Japanese islands and create a more powerful and centralized government.

Summary of Event

In the first half of the seventh century, the Soga Soga family , a powerful aristocratic family, were the main source of power at the Japanese court. Through their support of Buddhism and other continental innovations, they were able to eclipse the power of other major clans such as the Nakatomi and Mononobe and to hold sway over the court. Between 622 and 645, the imperial family was under the direct influence of Soga Emishi Soga Emishi , who became the head of the clan as well as great minister in 622. The power of the Soga family over the court was so great that Emishi was able to appoint imperial successors and ensure that they were married to Soga daughters. Emishi continued to flaunt his power by building a tomb of a magnitude that had previously been reserved for members of the imperial family and by murdering rivals who stood in his way. [kw]Adoption of Nengo System and Taika Reforms (645-646) [kw]Nengo System and Taika Reforms, Adoption of (645-646) Nengo system Taika reforms Japan;645-646: Adoption of Nengo System and Taika Reforms[0380] Laws, acts, and legal history;645-646: Adoption of Nengo System and Taika Reforms[0380] Government and politics;645-646: Adoption of Nengo System and Taika Reforms[0380] Soga Emishi Soga Iname Naka no Ōe Fujiwara Kamatari

This behavior as well as the reportedly crude and arrogant conduct of Emishi’s son Soga Iname Soga Iname , coupled with the desire of other important families such as the Nakatomi Nakatomi to restore the power that the Soga had usurped, fomented a conspiracy against the Soga that took shape in 644. Prince Naka no Ōe Naka no Ōe , interested in restoring the power of the imperial family, and the head of the Nakatomi family, better known as Fujiwara Kamatari Fujiwara Kamatari , who had seen his family’s influence eclipsed by the Soga, decided to act. Tradition holds that they had met at a kickball gathering, and the conspiracy developed from there. The pair planned to have the Soga leaders murdered and to gain control of the throne. It did not take them long to put their plan into action.

Emishi’s son Iruka was murdered, while at court and in the presence of the empress, by the henchmen of the conspirators. Within days, Emishi’s other supporters were rounded up and executed. Emishi then took his own life. The reigning empress, Kogyoku, was compelled to abdicate, and Imperial Prince Karu was enthroned. Naka no Ōe, who had played a leading role in the conspiracy, was named heir and effectively wielded power over the government. This chain of events paved the way for a series of reforms that would transform the nature of the Japanese government.

In 645, Japanese society existed in a relatively undeveloped state. The aristocracy was formed from the leaders of influential provincial families, the interests of which were often at odds. The imperial institution, which was the theoretical center of power in the country, did not have the legal or martial power to exert its influence over the whole of the land. The conspirators who took action against the Soga family were well aware of the weaknesses of this system and were well versed in the political theory of neighboring China, a philosophy that stressed order and strong central power. These theoretical precepts served as the basis for a wide reform movement that has come to be known collectively as the Taika reforms.

The name Taika, itself meaning “great reform,” was chosen as the reign name of Imperial Prince Karu when he was placed on the throne in 645. The process of adopting reign names for emperors, known as the nengo system, was used to play up the idea that dramatic change was at hand. The basis of these reforms was promulgated before the great nobles on June 19, 645, and they were forced to take an oath that they would serve the emperor with loyalty and not attempt to build up their own power at the expense of the central government. This enforced the idea that the emperor was now firmly at the center of Japanese political life and that the assembled ministers and nobles were his servants, and it is perhaps even more important than the specific institutional reforms that were to follow.

A generation before the conspiracy that ended the power of the Soga family, Shōtoku Taishi Shōtoku Taishi , himself both a Soga and an imperial prince, held power over the government as regent. Shōtoku Taishi introduced a number of reforms that brought Confucian and Buddhist ideas to Japanese politics. These earlier ideas served as the inspiration for the much more ambitious social reconstruction that Naka no Ōe and Fujiwara Kamatari introduced. In 646, a more direct and detailed reform edict than the previous precepts, outlining concrete reforms, was promulgated. Private ownership of land was abolished. In theory, all farmland in Japan belonged to the throne. This land, however, was to be evenly distributed among the people based on a survey of population. A new, more organized system of taxation was introduced as was a more logical system of impressed labor, designed to spare farmers the burden of extra work in the harvest and planting seasons. There were also regulations concerning common use of ponds and water and dealing with the garrisoning of areas of the countryside. Finally, the edict established a region in the middle of the country that was to act as a center of government, the first step toward the establishment of a permanent capital, a necessary precondition for the centralization of power. In addition, a system of prefecture governorships was established. Regulations as to the conduct of governors and what to do in cases of bribery and the like were also outlined. Smaller administrative districts—villages and townships—were also established. These reforms were all based on the Chinese administrative system. Other important reforms introduced during this period, including a fixed scale of court ranks, each with prescribed regalia and duties, were also based on Chinese models. In the short term, the Taika reforms succeeded in increasing the power of the imperial institution. However, there were many long-term consequences as well.


The Taika reforms had many faults. China was a far more advanced society than was the Japan of this period. The reforms, patterned largely on Chinese models, were in some ways unsuited to the political and geographical realities of the Japanese islands. Enforcing the egalitarian distribution of land proved troublesome. In addition, transient elements of the population proved impossible to register and tax. Despite their weaknesses, however, the impact of the Taika reforms was widespread.

Although the basic content was revised on a number of occasions and superceded in some respects, the reforms remained the theoretical basis for the administration of the Japanese archipelago until the early modern period. Despite the fact that the imperial family soon found itself under the influence of the Fujiwara, the new name of the Nakatomi family who had helped to overthrow the Soga, the imperial court was now unquestionably the center of political life in Japan. The reforms also provided the impetus for the establishment of Japan’s first permanent capital at Nara in 710.

The provision that farmers and administrators on the northern frontier should be allowed to keep weapons in order to defend themselves against raids by an indigenous people who were referred to as Emishi, gives scholars some insight into how a warrior culture was able to develop away from court influence. In addition, the concept of the illegality of private ownership of land also proved to be an important one in later years as it provided the basis for the complex system of landholding that emerged when provincial warrior families gained influence and came to dominate the court in the eleventh and twelfth centuries. In short, the Taika reforms not only created a strong imperial institution but also helped form the warrior society that was to become the main force in Japanese political life during the medieval period.

Further Reading
  • citation-type="booksimple"

    xlink:type="simple">Aston, W. G., trans. Nihongi: Chronicles of Japan from the Earliest Times to A.D. 697. 1896. Reprint. Tokyo: Charles E. Tuttle, 1972. The standard translation of one of the earliest works of Japanese history. Provides details about the plot that led to the downfall of the Soga family and the Taika reforms.
  • citation-type="booksimple"

    xlink:type="simple">Farris, William. Population, Disease, and Land in Early Japan, 645-900. Cambridge, Mass.: Harvard University Press, 1995. A detailed analysis of the impact of the Taika reforms on landholding in Japan.
  • citation-type="booksimple"

    xlink:type="simple">Friday, Karl. Hired Swords: The Rise of Private Warrior Power in Early Japan. Stanford, Calif.: Stanford University Press, 1992. Provides details concerning the military consequences of the Taika reforms and how they set the institutional basis for warrior power.
  • citation-type="booksimple"

    xlink:type="simple">Sansom, George. A History of Japan to 1334. Vol. 1. Stanford, Calif.: Stanford University Press, 1958. The first volume of Sansom’s three-volume study of Japanese history remains a detailed and authoritative work on the subject.

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