Kōgen
Kōgen (康元?) was a Japanese era name (年号, nengō,?, lit. "year name") after Kenchō and before Shōka. This period spanned the years from October 1256 to March 1257. The reigning emperor was Go-Fukakusa-tennō (後深草天皇?).
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Wikipedia
Kōgen (康元?) was a Japanese era name (年号, nengō,?, lit. "year name") after Kenchō and before Shōka. This period spanned the years from October 1256 to March 1257. The reigning emperor was Go-Fukakusa-tennō (後深草天皇?).