In the clause of December, 670 of Shilla Hongi (History of Shilla), "Samguk Sagi" (History of the Three Kingdoms), a history book of Korean Peninsula, there is a description that says 'Wakoku was renamed Nippon because the land is close to the place where the sun rises.'
また、朝鮮半島の史書『三国史記』「新羅本紀」文武王十年（670年）12月条には、「倭国、号を日本に更む。自ら言う、日出づるに近きを以て名を為す」とある。