AS201 Japan: Age of Gods/Kojiki Myths
Plain of High Heaven Takamagahara
Izanagi (Male) AND IZANAMI (Female) Deities
give birth to many deities, including the brother and sister:
Amaterasu-no-Omikoto and Susu-no-O (Sun Goddess and Storm God)
Ninigi-no-mikoto, Amaterasu's Grandson
Given 3 Sacred Treasures: Mirror, Sword, Jewels
and told to "Pacify the Land"
Ninigi's Grandson allegedly becomes Japan's first emperor, Emperor Jimmu or Jimmu Tenno,
but Jimmu is not historically verifiable; and he definitely did not emerge as a ruler in 660 BC!!
Perhaps Emperor Sujin is first verifiable ruler but most likely ruled in the Third Century AD, 219-249, not 97-30 BC as official chronology would have it.
Ojin Tenno 270-310, some 20 years later, might be a better candidate for the earliest Japanese monarch; maybe he was a renegade Puyo aristocrat who came over from Paekche or Koguryo and took over the Sujin line and moved the base from Kyushu to the Yamato Plain
Yuryaku tenno from 456-479 AD or possibly even as late as
Keitai Tenno 507-531 meaning AFTER early Japanese state had formed it was hi-jacked by people with superior military technology and state-building experience