Saimei period

The Saimei period is a chronological timeframe during the Asuka period of Japanese history. The Saimei period describes a span of years which were considered to have begun in the 1315th year of the Yamato dynasty.

This periodization is congruent with the reign of Empress Saimei, which is traditionally considered to have been from 655 through 662.

The adoption of the Sexagenary cycle calendar (Jikkan Jūnishi) in Japan is attributed to Empress Suiko in 604; and this Chinese calendar continued in use throughout the Saimei period.

In 645, the system of Japanese era names (年号,, nengō,^?, lit. "year name") was introduced. However, after the reign of Emperor Kotoku, this method of segmenting was temporarily abandoned or allowed to lapse. This interval continued during the Saimei period.

Neither Empress Saimei's reign nor the Saimei periodization are included in the list of nengō for this explicit duration of time, which comes after Hakuchi and before Suchō.

In the post-Taika or pre-Taihō chronology, the first year of Empress Saimei's reign (斉明天皇元年 or 斉明天皇1年) is also construed as the first year of the Saimei period (斉明1年).

Non-nengō periods in the pre-Taihō calendar were published in 1880 by William Bramsen. These were refined in 1952 by Paul Tuschihashi in Japanese Chronological Tables from 601 to 1872.

The pre-Tahiō calendar included two non-nengō gaps or intervals in the chronological series:

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