During the Heian period and other pre-modern eras of Japanese History, temporal differences were not identified by the year, solar nor lunar.
Rather, significant events, like a famine or particularly brutal storm initiated a new “era” that uniquely marked the following period until the next era began.
Later this tradition, dictating that a new era had began, was used by Emperors to add weight to their legitimacy and communicate that change was coming.
Connections
Link Explanation: This is a loose connection, but I think it is interesting how the measurement of time, across long periods can vary between different cultures. I had never considered that a culture may not use years to measure time. Even before knowing that the earth revolves around the sun, the passing of 4 seasons would indicate that a year has taken place. In a society dependent on agriculture, it seems like the obvious methodology. Perhaps this indicates the Heian court’s disconnection from the common people. Regardless, despite the differences in unit of measurement, time, history and context are inescapable for all conscious creatures.
Reference
� The Diary of Lady Murasaki