Japanese calendar and time
Japanese Eras
In modern times, a new era is declared at the enthronement of a new emperor, which is why 2019, the year Emperor Naruhito was enthroned, is the first year of the Reiwa Era. In ancient times, a new era would be declared to account for some major event such as a palace fire or an epidemic, which is why Emperor Ichijō was emperor throughout five full eras. This story takes place in the Chōhō Era.
The Tangled Spirits novels take place in the Heian Period, which historians declare began in 794 CE when Emperor Kanmu moved the capital from Nagaoka-Kyo to Heian-Kyo, and is considered to have ended in 1185 CE after years of conflict between Taira and the Minamoto clans, resulting in the fall of the Fujiwara clan from power, and creating the bakufu, also known as shogunate, a military government. There were 51 named eras within the Heian Period.
Months
Under the lunar calendar, the new year starts with the first new moon after January 21, so the year often begins in February, in which case February (the 2nd month in Gregorian Calendar) would be named First Month in the lunar calendar.
In ancient Japan, the numbered month names were most often used, but they also had more interesting month names. I've seen quite a few variations in what the old names meant, so I have chosen the definition that matches the lunar calendar month. For example Kisaragi is often defined as Month of Clothes, the logic being that one wears more clothes in February, but under the lunar calendar, Kisaragi would be in March, when the capital Heian-Kyo (modern day Kyoto) weather would be suitable to make the switch to spring colors. So it really means the "month of changing clothes." For a more detailed explanation, see my blog post about Japanese month names. https://kvshanahan.com/blog/f/ancient-month-names-in-japan
Lunar Calendar Name Western English Name Ancient Japanese Name
1st Month February Mutsuki (Harmony)
2nd Month March Kisaragi (Seasonal Change of Clothing)
3rd Month April Yayoi (Plant Growth)
4th Month May Uzuki (Deutzia Flowers )
5th Month June Satsuki (Planting Rice)
6th Month July Minazuki (No Water)
7th Month August Fumizuki (Literature)
8th Month September Hazuki (Leaves)
9th Month October Nagatsuki (Long Month)
10th Month November Kannazuki (Divine Spirits)
11th Month December Shimotsuki (Frost)
12th Month January Shiwasu (Running Priests)
Time of Day
The ancient clock was based on the Chinese zodiac, and was divided into twelve segments consisting of six daylight hours and six nighttime hours. In theory, each “hour” is two hours in length, but in order to ensure there would six hours of daylight and six hours of darkness, calendar-makers and time keepers were kept busy adjusting the length of each “hour” based on the time of year. In summer the six hours of daylight would become longer than two hours and the six hours of night would be correspondingly shorter.
5am-7am Hour of the Rabbit (Sunrise, Dawn)
7am-9am Hour of the Dragon
9am-11am Hour of the Snake
11am-1pm Hour of the Horse
1pm-3pm Hour of the Sheep
3pm-5pm Hour of the Monkey
5pm-7pm Hour of the Bird (Sunset, Dusk)
7pm-9pm Hour of the Dog
9am-11pm Hour of the Boar
11am-1am Hour of the Rat
1am-3am Hour of the Ox
3am-5am Hour of the Tiger