Birth of Heizei
Heizei, whose personal name is Ate, is born as the eldest son of the future Emperor Kanmu and Fujiwara no Otomuro.
Historical biography archive · Updated 2026-11-03
Heizei Biography and Timeline
Follow Heizei through 22 dated historical records for Japan.
Heizei, historical timeline
A chronological timeline drawn from matching World History Database records.
22Distinct records
1 of 1Page
774–824Years on this page
774
785
Named Crown Prince
Prince Ate becomes crown prince after Prince Sawara is removed from the succession.
806
Central Offices Reorganized
Heizei's government consolidates and reorganizes central offices in an effort to simplify administration and reduce unnecessary expenditure.
Role range: 0806-0809
Fiscal Recovery Policy
Heizei's government seeks to repair state finances strained by capital construction and the military campaigns of Emperor Kanmu's reign.
Role range: 0806-0809
Imperial Guard Reorganization
During Heizei's reign, the imperial guard organization is restructured into left and right guard commands.
Role range: 0806-0809
Observation Commissioners Established
Heizei establishes observation commissioners to inspect regional administration and submit proposals concerning local government.
Role range: 0806-0809
Succession
Heizei succeeds his father, Emperor Kanmu, and becomes the fifty-first emperor in the traditional Japanese succession.
Role range: 0806-0809
Tamuramaro Appointed Guard Commander
Sakanoue no Tamuramaro receives senior command in the reorganized imperial guard during Heizei's reign.
Role range: 0806-0809
809
Retirement to Heijo-kyo
The retired Heizei moves to the former capital at Heijo-kyo in Nara after his abdication.
Abdication
Heizei abdicates because of illness in favor of his younger brother, who becomes Emperor Saga.
Role range: 0806-0809
Prince Takaoka Named Crown Prince
Emperor Saga designates Heizei's son Prince Takaoka as crown prince after succeeding to the throne.
Saga Enthroned
Following Heizei's abdication, his younger brother takes the throne as Emperor Saga.
810
Kusuko Removed from Office
Emperor Saga removes Fujiwara no Kusuko from her court office as the confrontation with Heizei's faction reaches its crisis.
Attempted Move to the Eastern Provinces
Heizei attempts to leave Nara with supporters and seek military backing in the eastern provinces, but forces loyal to Saga block the plan.
Heizei Takes Buddhist Tonsure
After the failure of his political challenge to Emperor Saga, Heizei takes the tonsure and becomes a Buddhist monk.
Order to Restore Capital to Heijo
Heizei's faction attempts to move the imperial capital back from Heian-kyo to the old capital at Heijo-kyo.
Prince Takaoka Removed as Crown Prince
After the crisis, Heizei's son Prince Takaoka is removed as crown prince and replaced by Prince Otomo, the future Emperor Junna.
Saga Recalls Heizei Officials
Emperor Saga recalls officials serving the retired Heizei and moves to reassert control over the central administration.
Two Imperial Courts
Heizei continues intervening in state affairs from Nara, creating a political situation later described as two competing imperial courts.
811
Withdrawal from Politics
After the 810 confrontation, the retired Heizei no longer plays an active role in imperial politics.
822
Esoteric Buddhist Initiation
Heizei receives an esoteric Buddhist initiation associated with the monk Kukai during his retirement.
824
Death of Heizei
Heizei dies in 824 and is buried at the Yamamomo imperial mausoleum in present-day Nara.
Records, sources and methodology
These dates and descriptions come from the historical_events database. Exact duplicate records have been collapsed. Names are grouped by the country, Name 2 and Name 1 fields; records with missing Name 2 cannot be reliably assigned to an individual biography. Check the underlying sources before formal citation.