After the capitulation of the Shogunate and the Meiji Restoration, the inhabitants including the Shogun Tokugawa Yoshinobu had to vacate the premises of Edo Castle. In the second year of Meiji, on the 23rd day of the 10th month (1868), the emperor left Kyoto Imperial Palace for Tokyo. The Edo castle compound became the new imperial residence and was renamed Tokyo Castle (東京城 Tokyo-jou) in October, 1868, and then renamed Imperial Castle (皇城 Koujou) in 1869. Previous fires had already destroyed the Honmaru area containing the old donjon (which itself had burned in the 1657 Meireki fire). On the night of 5 May 1873 a fire consumed the Nishinomaru Palace (which had been the shogun's residential palace), and this area became the site of the new imperial Palace Castle (宮城, Kyuujou), built in 1888.
In the Meiji era, most of the structures from Edo Castle disappeared, either to make way for other buildings or due to earthquakes and fire. For example, the wooden double bridges (二重橋) over the moat were replaced with stone and iron bridges. The architecture of the imperial palace and buildings constructed in the Meiji era was from the outside pure traditional Japanese architecture, while the interiors were an eclectic mixture of Japanese and European elements fashionable in the 19th century. Most of the buildings were constructed from wood. The ceilings of the grand chambers were coffered with Japanese elements; however, Western furniture such as chairs and tables, together with heavy curtains, were used. For the floors, the public rooms had parquet or carpet but the residential spaces used the traditional tatami mats.
The main audience hall was the central part of the palace. It was the largest building, in which guests were received for public events. The floor space was more than 223 tsubo (1 tsubo is 3.306 square meters). In the interior, the coffered ceiling was traditional Japanese-style, while the floor was parquetry. The roof was styled as in the Kyoto Imperial Palace, but was covered with copper plates (in order to make it fireproof) rather than Japanese cypress shingles.
In the late Taisho and early Showa eras, more buildings were added that were constructed with concrete, such as the headquarters of the Imperial Household Ministry and the Privy Council. These structures were more modern in appearance with only some token Japanese elements.
From 1888 to 1948, it was called Palace Castle (宮城 Kyuujou). On the night of 25 May 1945 most of the structures of the Imperial Palace were destroyed in the Allied fire-bombing raid. It was from the basement of the concrete library that Emperor Showa declared the capitulation of Japan in August 1945. Due to the large-scale destruction of the Meiji-era palace, the new main palace hall (Kyuuden 宮殿) and residences were constructed on the western part of the site in the 1960s. The whole area was renamed literally Imperial Residence (皇居) in 1948. The east part was renamed East Garden (東御苑) and has been a public park since 1968.
The present imperial palace encompasses the retrenchments of the former Edo Castle where the Honmaru (inner citadel), Ninomaru (second citadel), Nishinomaru (west citadel), Sannomaru (third citadel), and Fukiage Gardens existed. A palace for various imperial court functions is located in the Nishinomaru and the residence of the emperor and empress is located in the Fukiage Gardens.