850s in Japan

was a after ''Ten'an and before Gangyō.'' This period spanned the years from April 859 through April 878. The two reigning emperors were and .

, also known as Kajō, was a after Jōwa and before Ninju. This period spanned the years from June 848 through April 851. The reigning emperors were and .

was a after Ninju and before ''Ten'an.'' This period spanned the years from November 854 through February 857. The reigning emperor was .

was a after Kashō and before Saikō. This period spanned the years from April 851 through November 854. The reigning emperor was .

was a after Saikō and before Jōgan. This period spanned the years from February 857 through April 859. The reigning emperors were and .

879 Book by Fujiwara no Mototsune