In the genealogy of Mochizuki (望月氏) clan, he is the grandson of deity Kamimusubi (神産巣日) and the ancestor of a clan of the ancient kingdom of Ki-no-kuni-miyatsuko (紀国造), which is modern-day Wakayama Prefecture, which in the Shinsen Shōjiroku (新撰姓氏録, "New Selection and Record of Hereditary Titles and Family Names").

However, in another genealogical text, Ame-no-Tajikarao appears to be the child of Ame-Yagokoro-Omoikane-no-mikoto (天八意思兼命 - another name of the deity Omoikane (思兼 or 思金), which is the honored distant ancestor of the Achinohōri clan.

Although in relation to this clan, inscribed in another text, the child of the deity Omoikane, Ame-no-Uwaharu-no-mikoto (天表春命), the name of Ame-no-Tajikarao is nowhere to be seen in the genealogy tree.

His own Shinto priests think he was originally a protector of agriculture (maybe because he brought back sunlight to the world, or maybe because peasants need fitness to work in the fields).

The name Ame-no-tajikarao carries the connotation of a male god with extreme and surmounting physical brute strength.