After that, Honmaru (the keep of a castle) of Edo-jo castle was divided into the government office of the Edo bakufu (Japanese feudal government headed by a shogun) named "Omote", the Shogun's office to administrate political affairs named "Nakaoku" and the Shogun's private residence named "O-oku".
以後、本丸は江戸幕府政庁の「表」、将軍が政務を執る「中奥(奥)」、将軍の私邸「大奥」に区分された。