He launched a military expedition from Hyūga near the Seto Inland Sea, captured Yamato, and established this as his center of power.

In modern Japan, Emperor Jimmu's legendary ascension is marked as National Foundation Day on February 11.

[2] In the reign of Emperor Kanmu (737–806),[4] the eighth-century scholar Ōmi no Mifune retroactively designated rulers before Emperor Ōjin as tennō (天皇, "heavenly sovereign"), a Japanese pendant to the Chinese imperial title Tiān-dì (天帝), and gave several of them including Jimmu their posthumous names.

The Imperial House of Japan traditionally based its claim to the throne on its putative descent from the sun-goddess Amaterasu via Jimmu's great-grandfather Ninigi.

As they reached Naniwa (modern-day Osaka), they encountered another local chieftain, Nagasunehiko ("the long-legged man"), and Itsuse was killed in the ensuing battle.

The record in the Nihon Shoki of Emperor Jimmu states that his armed forces defeated a group of Emishi (蝦夷, 'shrimp barbarians') before his enthronement.

Upon scaling a Nara mountain to survey the Seto Inland Sea he now controlled, Jimmu remarked that it was shaped like the "heart" rings made by mating dragonflies, archaically akitsu 秋津.

It is generally thought that Jimmu's name and character evolved into their present shape just before[18] the time in which legends about the origins of the imperial dynasty were chronicled in the Kojiki.

[26] Before and during World War II, expansionist propaganda made frequent use of the phrase hakkō ichiu, a term coined by Tanaka Chigaku based on a passage in the Nihon Shoki discussing Emperor Jimmu.

[28] For the 1940 Kigensetsu celebration, marking the supposed 2,600th anniversary of Jimmu's enthronement, the Peace Tower[29] was constructed in Miyazaki.

[30] The same year numerous stone monuments relating to key events in Jimmu's life were erected around Japan.

In 1941 the Japanese government charged the one historian who dared to challenge Jimmu's existence publicly, Tsuda Sōkichi.

[34][2][35] Today most modern scholars agree that the traditional founding of the imperial dynasty in 660 BC is a myth and that Jimmu is legendary.

[44] The Japanese historian Ino Okifu identifies Emperor Jimmu with the Chinese alchemist and explorer Xu Fu, a hypothesis supported by certain traditions in Japan and regarded as possible by some modern scholars.

[45][46] The Yayoi period, during which significant changes in Japanese metallurgy and pottery occurred, started around the time of his supposed arrival.

Unless otherwise noted (as BC), years are in CE / AD  * Imperial Consort and Regent Empress Jingū is not traditionally listed.