Kōshō (康正) was a Japanese era name (年号, nengō, lit. "year name") after Kyōtoku and before Chōroku. This period spanned the years from July 1455 through September 1457.[1] The reigning emperor was Go-Hanazono-tennō (後花園天皇).[2]
Change of Era
1455Kōshō gannen (康正元年): The era name was changed to mark an event or a number of events.