The Isshi coup and the Taika reforms

For four generations the Soga ministers had dominated the Yamato court, and in 643 Soga no Iruka destroyed the family of Prince Yamashiro no Ōe, the son of Prince Shōtoku. Nakatomi no Kamatari and Prince Naka no Ōe, son of Empress Kōgyoku, won over Iruka’s kinsman Soga no Kurayamada no Ishikawa no Maro. On 10 July 645, according to the Nihon shoki, while Ishikawa no Maro read out the memorial of the envoys of the three Korean kingdoms in the Great Hall of the Itabuki palace, the prince and Saeki no Komaro struck Iruka with swords; the wounded minister pleaded before the throne, but the empress withdrew into the palace, and Komaro and Wakainukai no Amita cut him down. Naka no Ōe occupied the Soga temple Hōkō-ji (Asuka-dera) as a stronghold, and the next day Iruka’s father Emishi killed himself, burning the chronicles Tennōki and Kokki, of which only the Kokki was snatched from the flames. Some Japanese historians regard the famous scene as a literary creation of the sources, which glorify Naka no Ōe and Kamatari.

On 12 July Kōgyoku abdicated in favour of her brother Prince Karu, Emperor Kōtoku; Naka no Ōe became crown prince, Abe no Uchimaro and Ishikawa no Maro ministers of the left and right, Kamatari Inner Minister, and the monk Min and Takamuko no Kuromaro, who had studied in China, national scholars. On 17 July the court swore an oath under a great zelkova tree and adopted the era name Taika, ‘Great Change’, traditionally regarded as the first Japanese era name; at the end of the year the capital moved to Naniwa. The edict proclaimed on New Year’s Day 646 set out four principles: the abolition of private estates and of the hereditary groups of workers owned by the court and the clans; a capital, provinces and districts under appointed officials; household registers and the periodic allotment of rice land; and a uniform system of taxes and labour dues.

The text of the edict preserved in the Nihon shoki, compiled in 720, was rewritten in the language of the later law codes: in the 1950s the ‘kōri debate’ turned on the word for district, and a wooden tablet dated 699 found at Fujiwara in 1967 proved that districts were still called hyō until the Taihō code of 701. Some historians then doubted that any reform had taken place, but since the late 1970s, supported by excavations of the Naniwa palace and a tablet dated 648 found there in 1999, most accept a real political change under Kōtoku while reading the edict critically. The reforms went slowly — in 653 Naka no Ōe took the court back to Asuka, leaving Kōtoku alone at Naniwa — and were completed only by the Taihō code.