Almost all era names were literary and employed exactly two characters.

From 1868 only one era name has been used by each emperor.

Since 1868 each emperor has been known posthumously by his era name.

His grandfather and father also employed era names, though not continuously.

The existence of more than one era name at a time often reflected political unrest.

Unlike some of these other similar systems, Japanese era names are still in use.

Government offices usually require era names and years for official papers.

Since then, era names have been used continuously up through the present day.

He also changed era name and established an imperial government.

The years of Kameyama's reign include more than one era name.