The Asuka period in Japan began around 538 CE with the introduction of Buddhism from the Korean kingdom of Baekje.^[21] This period was named after its de facto imperial capital, Asuka.^[23] Buddhism coexisted with the native Shinto religion in a fusion known as Shinbutsu-shūgō.^[22] The Soga clan, proponents of Buddhism, assumed control of the government in the 580s and ruled indirectly for about sixty years.^[24] Prince Shōtoku, serving as regent from 594 to 622, was instrumental in the period’s development. He authored the Seventeen-article constitution, inspired by Confucian principles, and attempted to introduce a merit-based civil service system called the Cap and Rank System.^[25]

In 645, the Soga clan was overthrown in a coup by Prince Naka no Ōe and Fujiwara no Kamatari, the founder of the Fujiwara clan.^[28] leading to significant administrative changes known as the Taika Reforms. Initiated with land reform based on Confucian ideologies from China, the reforms aimed to nationalize all land for equitable distribution among cultivators. The reforms also called for the compilation of a household registry for taxation.^[29] The overarching goal was to centralize power and bolster the imperial court, drawing heavily from China’s governmental structures. Envoys and students were sent to China to study various aspects including writing, politics, and art.

The period after the Taika Reforms saw the Jinshin War of 672, a conflict between Prince Ōama and his nephew Prince Ōtomo, both contenders for the throne. This war led to further administrative changes, culminating in the Taihō Code.^[28] This code consolidated existing laws and outlined the structure of the central and local governments, leading to the establishment of the Ritsuryō State, a system of centralized government modeled after China that persisted for approximately five centuries.^[28]