Japanese imperial year

The Japanese imperial year (皇紀, kōki^?) or "national calendar year" is a unique calendar system in Japan. It is based on the legendary foundation of Japan by Emperor Jimmu in 660 BC.Kōki the long history of Japan and the Imperial dynasty.

Kōki dating was used as early as 1872, shortly after Japan adopted the Gregorian calendar system.

The Summer Olympics and Tokyo Expo were planned as events in 1940 (Kōki 2600); but the international games were not held because of the Second Sino-Japanese War.

The Imperial Japanese Army (IJA) and Imperial Japanese Navy (IJN) used the Kōki system for . For example,

The Proclamation of Indonesian Independence used the imperial year.

In Japan today, the system of counting years from the of Emperor Jimmu has been officially abandoned.

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