The era after the enthronement of Emperor Jimmu (神武天皇即位紀元, Jinmu-tennō sokui kigen), colloquially known as the Japanese imperial year (皇紀, kōki) or "national calendar year" is a unique calendar system in Japan.[1] It is based on the legendary foundation of Japan by Emperor Jimmu in 660 BC.[2] Kōki emphasizes the long history of Japan and the Imperial dynasty.[3] The Gregorian year 2024 is Kōki 2684.