“Tenshu”: Japan’s Castle Keeps as a Symbol of Powerful Leaders

This is thought to be the oldest existing illustration that depicts the remains of Azuchi Castle and appears in Nihon kojō ezu gōshū azuchi kojō-zu, a pictorial map of old Japanese castles created in the mid-to-late Edo period (1603–1868). (Courtesy National Diet Library)

Edojō go-honmaru go-tenshukaku tatekata no zu, a structural plan of the honmaru tenshu at Edo Castle which was completed in 1638 under the third Tokugawa shōgun Iemitsu. (Courtesy the Tokyo Metropolitan Central Library Special Collection Room)

The sanjū yagura at Hirosaki Castle, unofficially recognized by the Tokugawa shogunate. (© Pixta)