The Jitō period is a chronological timeframe during the Asuka period of Japanese history. The Jitō period describes a span of years which were considered to have begun in the 1347th year of the Yamato dynasty.
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 Jitō period.
In 645, the system of Japanese era names (年号,nengō, "year name") was introduced. However, after the reign of Emperor Kōtoku, this method of segmenting time was temporarily abandoned or allowed to lapse. This interval continued during the Jitō period.
Neither Empress Jitō's reign nor the Jitō periodization are included in the list of nengō for this explicit duration of time, which comes after Suchō and before Taihō.
In the post-Taika or pre-Taihō chronology, the first year of Empress Jitō's reign (持統天皇元年 or 斉持統皇1年) is also construed as the first year of the Jitō period (持統1年).
Non-nengō periods in the pre-Taihō calendar were published in 1880 by William Bramsen. These were refined in 1952 by Paul Tsuchihashi in Japanese Chronological Tables from 601 to 1872.
The pre-Tahiō calendar included two non-nengō gaps or intervals in the chronological series:
686 (Jitō 1): Emperor Temmu dies, but his son and heir was deemed too young to receive the succession (senso). Instead, the mother of the heir succeeds the Chrysanthemum Throne (senso) as Empress Jitō until her son would grow mature enough to accept senso and sokui.
686 (Jitō1): A new period is marked by the beginning of the reign of Empress Jitō, but the end of the previous nengō Hakuchi 6 (654) does not imply the commencement of a new nengō in the succeeding reigns.
688 (Jitō 3): Prince Kusakabe, Empress Jitō's son, dies at age of 27.
689 (Jitō 4): Empress Jitō formally accedes to the Chrysanthemum Throne (sokui) on the first month, first day.
697 (Jitō 11): Prince Karu, the Empress' grandson, is made the Heir Apparent on the second month, 16th day. The Empress gets sick. She abdicates the Chrysanthemum Throne in favor of Prince Karu on the eighth month, first day.
Empress Jitō distributed rice to the aged throughout the years of her reign.
^Murray, p. 402, p. 402, at Google Books; the system of counting from year-periods (nengō) do not ordinarily overlap with the reigns of the early monarchs; and generally, a new one was chosen whenever it was deemed necessary to commemorate an auspicious or ward off a malign event.
^ abBrown, p. 270, p. 270, at Google Books; excerpt, "The eras that fell in this reign were: (1) the remaining seven years of Shuchō [(686+7=692?)]; and (2) Taika, which was four years long [695-698]. (The first year of this era was kinoto-hitsuji .) ...In the third year of the Taka era , Empress Jitō yielded the throne to the Crown Prince."
Bramsen, William. (1880). Japanese Chronological Tables: Showing the Date, According to the Julian or Gregorian Calendar, of the First Day of Each Japanese Month, from Tai-kwa 1st year to Mei-ji 6th year (645 AD to 1873 AD): with an Introductory Essay on Japanese Chronology and Calendars. Tokyo: Seishi Bunsha. OCLC 35728014