Keio

Keiō (慶応^?, historically 慶應) was a Japanese era name (年号,, nengō,^?, literally "year name") after Genji and before Meiji. The period spanned the years from May 1865 to October 1868. The reigning emperors were Kōmei-tennō (孝明天皇^?) and Meiji-tennō (明治天皇^?).

Keio University, which was initially established in 1858 (Ansei 5), seven years before the beginning of the Keiō era, is named after this era. This is the oldest existing institution of higher learning in Japan.

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