Emperor Heizei

, also known as Heijō-tennō, was the 51st emperor of Japan, according to the traditional order of succession. Heizei's reign lasted from 806 to 809.

Traditional narrative Heizei was the eldest son of the Emperor Kanmu and empress Fujiwara no Otomuro. Heizei had three empresses and seven sons and daughters.

Heizei is traditionally venerated at his tomb; the Imperial Household Agency designates , in Nara, as the location of Heizei's mausoleum. Although one of the largest kofun monuments in Japan, archaeological investigations in 1962–1963 indicate that it was constructed in the early 5th century, and that portions of it were destroyed during the construction of Heijō-kyō, calling into question the designation by the Imperial Household Agency.

Events of Heizei's life Before he ascended to the throne, his liaison with Fujiwara no Kusuko, the mother of his one consort, caused a scandal. Because of this scandal his father considered depriving him of the rank of crown prince.

785: : Heizei was appointed Crown Prince at the age of 12. April 9, 806 : In the 25th year of Emperor Kanmu's reign, he died; and despite an ensuing dispute over who should follow him as sovereign, contemporary scholars then construed that the succession (senso) was received by his son. Shortly thereafter, Emperor Heizei is said to have acceded to the throne (sokui).

His title Heizei was derived from the official name of the capital in Nara, Heizei Kyō.

During Heizei's reign, the bodyguards were reorganized; the existing Imperial Bodyguards became the Left Imperial Bodyguards, while the Middle Bodyguards became the Right Imperial Bodyguards. Both sides were given a new Senior Commander; at this time Heizei appointed Sakanoue no Tamuramaro (758–811) as Senior Commander of the Imperial Bodyguards of the Right.

809 : After a reign of four years, Heizei fell ill; and fearing that he would not survive, Heizei abdicated in favor of his younger brother, who would later come to be known as Emperor Saga. August 5, 824 : Heizei died at age 51, 14 years after he had abdicated due to illness.

Era of Heizei's reign The years of Heizei's reign are encompassed within one era name (nengō). Daidō (806–810)

Kugyō is a collective term for the very few most powerful men attached to the court of the Emperor of Japan in pre-Meiji eras.

In general, this elite group included only three to four men at a time. These were hereditary courtiers whose experience and background would have brought them to the pinnacle of a life's career. During Heizei's reign, this apex of the Daijō-kan included: Sadaijin (not appointed) Udaijin, Miwa-no-Oh or Miwa-no-Ohkimi (神王), 798–806. Consort (Hi): Imperial Princess Asahara (朝原内親王; 779–817), Emperor Kanmu’s daughter Consort (Hi): Imperial Princess Ōyake (大宅内親王; d.849), Emperor Kanmu’s daughter Consort (Hi):: Imperial Princess Kan'nabi (甘南美内親王; 800–817), Emperor Kanmu’s daughter Shōshi Court lady (Naishi-no-kami): , former wife of Chūnagon Fujiwara no Tadanushi