Iwarehiko no Mikoto and his brothers were born in Takachiho, Hyuga, the southern part of Kyūshū, present Miyazaki prefecture.
They moved eastward to find a location more appropriate for administering the entire country. They encountered a local chieftain, Nagasunehiko and his men. After a fierce battle Iwarehiko no Mikoto beat Nagasunehiko side.
They moved to Yamato. At the foot of Mt. Unebi, one of the three Yamato mountains there is a place called Kashihara. There Iwarehiko no Mikoto ascended the throne. He became the first emperor of Japan Jimmu and started his reign.