Emperor Jimmu was the legendary first emperor of Japan according to the Nihon Shoki and Kojiki. His ascension is traditionally dated as 660 BC. In Japanese mythology, he was a descendant of the sun goddess Amaterasu, through her grandson Ninigi, as well as a descendant of the storm god Susanoo. He launched a military expedition from Hyūga near the Seto Inland Sea, captured Yamato, and established this as his center of power. In modern Japan, Emperor Jimmu's legendary accession is marked as National Foundation Day on February 11. There is no evidence to suggest that Jimmu existed. However, there is a high probability that there was a powerful dynasty in the vicinity of Miyazaki Prefecture during the Kofun period.