In Japanese history, besides the Imperial Court ruled by the Emperor, existed military governments such as Bakufu (Japanese feudal government headed by a shogun): bakufu was headed by a shogun (a barbarian-quelling generalissimo in official name) who was called at times "the King of Japan" or "the Emperor of Japan", and therefore, there are various discussions and understandings as to what a capital is defined as, including both the capital systems of Tokyo and Kyoto.
日本では歴史上天皇による朝廷の他に、国際的には時に「日本国王」「日本国大君」とも称された征夷大将軍による幕府のような武家政権が存在したことや、東京と京都の両京制などの面から首都の議論があり、様々な首都論・首都認識がある。