Shinto reckoning of ritual time has been much influenced by Chinese traditions. As early as 675 C.E., religious Daoism had made a significant impact on the Japanese imperial court, which formally adopted many Daoist practices. Most importantly, the court set up a bureau of divination, called the Onmyoryo (“Office of Yin-Yang”), based on Daoist principles. One of the Onmyoryo’s chief functions was to establish a liturgical calendar that patterned earthly life on the rhythms of the cosmos. This lunar calendar retains all the main features of its Chinese model, including the cycles of sixty years based on the combinations of twelve “branches” and ten “stems” (see the sections on Daoism and Confucianism). The Japanese call their Chinese version of the lunar calendar Kyureki, as distinct from the modern solar calendar adopted in 1872, the Shinreki. An early formal cycle of annual observance, called the nenchu gyoji, literally “year-round-discipline-rituals,” developed as early as the tenth century C.E. Imperial authorities promulgated it in a vast historical record called the Engi-shiki (“Institutes of the Engi Era,” 901-923 C.E.), an essential source of information about Shinto ritual in general. Japan’s lunar calendar needs to tuck in an extra month every three years or so.

Prior to the nineteenth century, many Shinto shrines maintained their own calendars of events, including uniquely regional and local festivities. Today some major events still take place according to various ways of adapting the lunar calendar to fit the solar. For example, some festivals now occur on the same numbered day within the same numbered month, but transferred to the solar reckoning. In other words, a festival that fell on the seventh day of the seventh lunar month now falls on July 7. Some festivals are now dated by keeping the day date but adding a solar month, so that a celebration once held on the seventh day of the seventh month now occurs on August 7. Finally, and more rarely, a few days retain their lunar dating completely, so that they rotate backward against the solar year. From the solar point of view, therefore, these are moveable feasts. Since the late nineteenth century, the timing of the major festivals has been coordinated so that all the larger shrines observe them at the same time. But there are still many distinctive local and regional festivities attached to individual shrines, such as the rituals dedicated to the patron deities of particular places. In addition to the liturgical calendar, an important related feature is the Japanese custom of dividing history according to imperial reigns or epochs. Emperor Hirohito died in 1989, ending the Showa era, and his son Akihito’s accession inaugurated the Heisei epoch.