The Taika Reforms were a set of doctrines established by Emperor Kōtoku in the year 645. They were written shortly after the death of Prince Shōtoku and the defeat of the Soga clan, uniting Japan. The reforms also artistically marked the end of the Asuka period and the beginning of the Hakuhō period. Crown Prince Naka no Ōe, Nakatomi no Kamatari, and Emperor Kōtoku jointly embarked on the details of the Reforms. Emperor Kōtoku then announced the era of "Taika" (大化), or "Great Reform".

Emperor Kōtoku was the 36th emperor of Japan, according to the traditional order of succession.