Emperor Heizei (平城天皇, Heizei Tennō, 774 - August 5, 824) was the fifty-first emperor of Japan, according to the traditional order of succession, and reigned from 806 to 809.

His personal name is Prince Ate and he is also sometimes referred to as Emperor Heijō (Heijō Tennō).

The name Heizei comes from the official name of Nara, Heizei-kyō, and he was often referred to as Nara no Mikado ("the emperor of Nara").

Emperor Heizei Genealogy

Heizei was the son of Emperor Kanmu and Fujiwara no Otumoro. He had 4 wives, and 7 imperial children born from ladies of the court:

• Fujiwara no Tarashiko/Obiko, died in 794; daughter of Fujiwara no Momokawa, received the posthumous title of empress
• Princess Asahara, her half-sister, born in 779; died in 817; daughter of emperor Kammu and princess Sakahito
• Princess Oyake, his half-sister, born in 788, died in 849; daughter of emperor Kammu and Tachibana no Tsuneko
• A daughter of Fujiwara no Tadanushi
• Fujiwara no Kusuko, died in 810; daughter of Fujiwara no Tanetsugu; nicknamed Naishi no Kami.

Fujii no Toshi (Fujiko), daughter of Fujii no Michiyori; court lady, mother of :

• Prince Abo, born 792, died 842; married Princess Ito, his aunt (801-861), daughter of Emperor Kammu and Fujiwara no Heishi; from whom he had 2 sons:
• Prince Narihira, born in 825, died in 880
• Prince Yukihira, father of
• Princess Ayako, married to emperor Seiwa.

Ise no Tsugiko, born in 772, died in 812; daughter of Ise no Ona; court lady, mother of :

• Prince Takaoka, born in 799, died in 809; crown prince in 809; deposed in 810
• prince Kose, died in 882
• Princess Kamitsukeno, died in 842
• Princess Iso no Kami, died in 846
• Princess Ohara, died in 863; vestal princess of Ise from 806 to 809.

Ki no Iokazu, daughter of Ki no Kotsuo; court lady, mother of :

• Princess Enu, died in 835.

Emperor Heizei Biography

Before his accession to the throne, his affair with Fujiwara no Kusuko, the mother of one of his concubines, caused a scandal which almost cost him his rank of crown prince, his father considering the possibility of removing him from it.

However, he became emperor after his father's death in 806. In 809, ill, he abdicated in favor of his younger brother prince Kamino, who then became emperor Saga.

After his abdication, Heizei moved to Nara and planned to move the capital from Kyoto to Nara once again. Emperor Saga, pretending to agree with him, ignored this advice and tried to reduce the influence of the former emperor.

In 810, Heizei fomented a rebellion with Kusuko, but was defeated by the imperial army, led by the shogun Sakanoue no Tamuramaro.

Following this event, Kusuko committed suicide and Heizei became a Buddhist monk. His son, Crown Prince Takaoka is then stripped of his rank, and Saga appoints his own son as Crown Prince.

Kugyō (公卿)

• Emperor Heizei (平城天皇), r. 806-809 -- kugyō of Heizi-tennō [archive]
• Udaijin, Miwa ookimi or Miwa oh (神王), 798-806
• Udaijin, Fujiwara no Uchimaro (藤原内麿), 806-812