Daidō
Daidō was a Japanese era name after Enryaku and before Kōnin. This period spanned the years from May 806 through September 810. The reigning emperors were Emperor Heizei and Emperor Saga.
Change of era
November 16, 806 Daidō gannen: The new era name was created to mark an event or series of events. The previous era ended and the new one commenced in Enryaku 25, on the 18th day of the 5th month of 806.
Events of the ''Daidō'' era
April 9, 806 : In the 25th year of Emperor Kammu's reign, he died, and despite an ensuing dispute over who should follow him as sovereign, contemporary scholars then construed that the succession was received by his son. Shortly thereafter, Emperor Heizei is said to have acceded to the throne.May 18, 809 : In the 4th year of Emperor Heizei's reign, he fell ill and abdicated, and the succession was received by his second son, the eldest son having become a Buddhist priest. Shortly thereafter, Emperor Saga is said to have acceded to the throne.