Amatsu means Heaven or Nature. Tatara means the highest secret teaching system of Martial Arts and original Shintoism spirit.
The Amatsu Tatara Hibumi (secret scrolls) are special scrolls about all Martial Arts, Spiritualism and Humanism. These were written about 700 BC by the King of Mima as the history of Japan. Tatara Isuzu Hime-no-Mikoto was given these scrolls. She then married the first emperor Jinmu and gave these scrolls to the Ohtomo, Nakatomi and Mononobe families (families loyal to the Emperor).
In about 700 BC (or 500 BC, or 600 BC), The King Mima drifted from the ancient Babylonia Caldia Kingdom to Japan with three attendants and they lived on Miwayama mountain (Nara Area). He formed a good friendship with the chieftain of Japan Amaterasu Ohmikami and made great efforts in controlling Japan. This is why he was made a Kunitsu Omi Muraji (Minister).
King Mima brought the special Kubikazari (necklace) which was made of 72 Magatama (jewels). The Kubikazari was not only for just fashion which was the symbol of a King. It had very important meaning and was used for fortunetelling as well. King Mima presented it to Amaterasu.
Hiboko-no-Mikoto followed King Mima to Japan. Hiboko was a great Shaman and brought Tokusano Kandakara (ten kinds of Gods treasures) of Shikin. Shikin means Rei-jutsu (spiritual techniques by truth consciousness.).
In 500 BC or 550 BC, several hundred Buddhist Vader people of the Malay race attacked Japan and fought the emperors army of Miwayama. The emperor's army fought and defeated them. From the battle the Japanese emperor's army designed weapons, created how to use them, and also how to win (strategies). From that time until about 10 AD a special scroll was written; the Amatsu Tatara Hibumi-no-Ikkan (original main secret scroll of the Amatsu Tatara) which includes all special techniques, philosophies, Tenmon (heavens things), Chimon (earth things) and others.