Kōka

Kōka (弘化) was a Japanese era name (年号) after Tenpō and before Kaei. This period spanned the years from December 1844 through  February 1848. The reigning emperors were Ninkō-tennō (仁孝天皇) and Kōmei-tennō (孝明天皇).

Change of era

 * December 2, 1844 (Kōka gannen (弘化元年)): 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.