Taika (era)

 was a during the reign of Kōtoku. The Taika era immediately preceded the "Hakuchi era." This period spanned the years from August 645 through February 650.
History.
In 645, also known as , the new era name was created to mark the beginning of the reign of the emperor Kōtoku. The previous reign ended and the new one commenced in the fourth year after the beginning of Empress Kōgyoku's reign.
In Japan, this was the first nengō, derived from the Chinese system of eras ("nianhao"); although some scholarly doubt has been cast on the authenticity of "Taika" and "Hakuchi" as historically legitimate era names.
Timeline.
The system of Japanese era names was not the same as Imperial reign dates.