Who is the legendary first emperor of Japan?

The legendary first emperor of Japan was Emperor Jimmu.

Emperor Jimmu, also called Jinmu Tennō, is presented in Japanese tradition as the country’s first emperor. The Kojiki, compiled in 712, and the Nihon Shoki, completed in 720 or 721, describe his eastern expedition from Kyushu toward Yamato, where he established a center of power in what is now Nara Prefecture.

According to the origin narrative, Jimmu descended from the sun goddess Amaterasu through her grandson Ninigi. His traditional accession date is 660 BCE, and Japan’s National Foundation Day, February 11, commemorates that legendary founding. His posthumous name is commonly interpreted as meaning “divine warrior” or “divine might.”

The important qualification is that Jimmu is legendary, not historically verified. Modern historians find no reliable evidence that he existed, and the early imperial genealogies combine myth, political tradition, and possible memories of later state formation. Emperor Sujin is sometimes considered a possible historical figure, while Emperor Kinmei is generally treated as the first emperor with securely verifiable dates.