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.

[1] The reigning emperor was Go-Fukakusa-tennō (後深草天皇).

[2] This article about a Japanese era name is a stub.