Emperor Annei (安寧天皇, Annei-tennō); also known as shikitsuhikotamatemi no Mikoto; was the third emperor of Japan, according to the traditional order of succession.
No firm dates can be assigned to this emperor's life, but he is conventionally considered to have reigned from 549 to 511 B.C., near the end of the Jōmon period.
Modern scholars have come to question the existence of at least the first nine emperors; Annei's descendant, Emperor Sujin is the first that many agree might have actually existed. The name Annei-tennō was assigned to him posthumously by later generations.
Annei is regarded by historians as a "legendary emperor" and there is a paucity of information about him. There is insufficient material available for further verification and study. The reign of Emperor Kinmei (c. 509 – 571 AD), the 29th emperor, is the first for which contemporary historiography is able to assign verifiable dates; however, the conventionally accepted names and dates of the early emperors were not to be confirmed as "traditional" until the reign of Emperor Kanmu (737–806), the 50th sovereign of the Yamato dynasty.
In Kojiki and Nihonshoki only his name and genealogy were recorded. The Japanese have traditionally accepted this sovereign's historical existence, and an Imperial misasagi or tomb for Annei is currently maintained; however, no extant contemporary records have been discovered that confirm a view that this historical figure actually reigned. He is considered to have been the second of eight emperors without specific legends associated with them, also known as the "eight undocumented monarchs" (欠史八代,, Kesshi-hachidai).
Emperor Annei was either the eldest son or the only son of Emperor Suizei. Before his accession to the throne, he was known as Prince Shikitsu-hiko Tamatemi.
Jien records that he ruled from the palace of Ukena-no-miya at Katashiro in Kawachi in what would come to be known as Yamato Province.
This emperor's posthumous name literally means "steady tranquillity". It is undisputed that this identification is Chinese in form and Buddhist in implication, which suggests that the name must have been regularized centuries after the lifetime ascribed to Annei, possibly during the time in which legends about the origins of the Yamato dynasty were compiled as the chronicles known today as the Kojiki.
The actual site of Annei's grave is not known. This emperor is traditionally venerated at a memorial Shinto shrine (misasagi) in Nara.
The Imperial Household Agency designates this location as Annei's mausoleum. It is formally named Unebi-yama no hitsujisaru Mihodo no i no e no no misasagi.