was a after Tenpō and before Kaei. This period spanned the years from December 1844 through February 1848. The reigning emperors were and . Change of era December 2, 1844 (): The new era name of Kōka, meaning "Becoming Wide or Vast", was created to mark a fire at Edo Castle in Tenpō 15. The nengo was not changed concurrent with the accession of Emperor Komei; instead, the Kōka era was retained until about a year after the new emperor was enthroned. Events of the Kōka era 1847 (Kōka 4): A major earthquake was recorded. 1848 (Kōka 5): The last subscription noh of the premodern era. During these years, Hiroshige began making a series of prints showing beautiful women in contexts of famous places. Notes References Keene, Donald. (2005). Emperor of Japan: Meiji and his world, 1852-1912. New York: Columbia University Press. ; OCLC 57750432 Nussbaum, Louis Frédéric and Käthe Roth. (2005). Japan Encyclopedia. Cambridge: Harvard University Press. ; OCLC 48943301 External links National Diet Library, "The Japanese Calendar" -- historical overview plus illustrative images from library's collection Japanese eras 1840s in Japan