Legendary emperor Jimmu is credited with the founding of the Japanese state in 660 BCE.

Jimmu (according to the earliest written Japanese histories, produced in the eighth century) is the grandson of the mythical hero Hiko Hohodemi and of Toyotama, daughter of the sea god.

Born on the island of Kyushu, Jimmu is said to have conquered southern Honshu and established himself as ruler in the area of the Yamato plain.

(Archaeological evidence indicates that no unified political state exists in Japan during this era.

Modern historians attribute the legend of Emperor Jimmu to an imaginative account of the emergence of the Yamato state on Honshu in the third century CE.)