In the history of China a belief is recorded that the Japanese sovereigns are descended from a Chinese prince, Tai Peh, whose father wished to disinherit him in favour of a younger son. Tai Peh fled to Wu in the present Chekiang, and thence passed to Japan about 800 B.C. Another record alleges that the first sovereign of Japan was a son of Shao-kang of the Hsia dynasty (about 850 B.C.), who tattooed his body and cut off his hair for purposes of disguise and lived on the bank of the Yangtsze, occupying himself with fishing until at length he fled to Japan.
That Ninigi may have been identical with one of these persons is not inconceivable, but such a hypothesis refuses to be reconciled with the story of the fighting in Izumo which preceded the descent to Tsukushi. The much more credible supposition is that the Yamato Court, confronted by a formidable rebellion having its centre in Izumo, retired to Tsukushi, and there, in the course of years, mustered all its followers for an expedition ultimately led by the grandson of the fugitive monarch to restore the sway of his house. This interpretation of the legend consists with the fact that when Jimmu reached Yamato, the original identity of his own race with that of the then ruler of the province was proved by a comparison of weapons.
With regard to the legend of the ocean Kami, the rationalists conceive that the tribe inhabiting Tsukushi at the time of Ninigi's arrival there had originally immigrated from the south and had gradually spread inland. Those inhabiting the littoral districts were ultimately placed by Ninigi under the rule of Prince Hohodemi, and those inhabiting the mountain regions under the sway of Prince Hosuseri. The boats and hooks of the legend are symbolical of military and naval power respectively. The brothers having quarrelled about the limits of their jurisdictions, Hohodemi was worsted, and by the advice of a local elder he went to Korea to seek assistance. There he married the daughter of the Ocean King--so called because Korea lay beyond the sea from Japan--and, after some years' residence, was given a force of war-vessels (described in the legend as "crocodiles") together with minute instructions (the tide-ebbing and the tide-flowing jewels) as to their skilful management. These ships ultimately enabled him to gain a complete victory over his elder brother.