Capital of Japan

Tokyo, officially the Tokyo Metropolis, is the capital and most populous city in Japan. With a population of over 14 million in the city proper in 2023, it is one of the most populous urban areas in the world. The Greater Tokyo Area, which includes Tokyo and parts of six neighboring prefectures, is the most populous metropolitan area in the world, with 41 million residents as of 2024.

Lying at the head of Tokyo Bay, Tokyo is part of the Kantō region, on the central coast of Honshu, Japan's largest island. It is Japan's economic center and the seat of the Japanese government and the Emperor of Japan. The Tokyo Metropolitan Government administers Tokyo's central 23 special wards, which formerly made up Tokyo City; various commuter towns and suburbs in its western area; and two outlying island chains, the Tokyo Islands. Although most of the world recognizes Tokyo as a city, since 1943 its governing structure has been more akin to that of a prefecture, with an accompanying Governor and Assembly taking precedence over the smaller municipal governments that make up the metropolis. Special wards in Tokyo include Chiyoda, the site of the National Diet Building and the Tokyo Imperial Palace; Shinjuku, the city's administrative center; and Shibuya, a hub of commerce and business.

Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asian mainland, it is bordered to the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea in the south. The Japanese archipelago consists of four major islands alongside 14,121 smaller islands. Japan is divided into 47 administrative prefectures and eight traditional regions, and around 75% of its terrain is mountainous and heavily forested, concentrating its agriculture and highly urbanized population along its eastern coastal plains. With a population of over 123 million as of 2025, it is the world's 11th most populous country. Tokyo is the country's capital and largest city.

The first known habitation of the archipelago dates to the Upper Paleolithic, with the beginning of the Japanese Paleolithic dating to c. 36,000 BC. Between the 4th and 6th centuries, its kingdoms were united under an emperor in Nara and later Heian-kyō. From the 12th century, actual power was held by military aristocrats known as shōgun and feudal lords called daimyō, enforced by warrior nobility named samurai. After rule by the Kamakura and Ashikaga shogunates and a century of warring states, Japan was unified in 1600 by the Tokugawa shogunate, which implemented an isolationist foreign policy. In 1853, an American fleet forced Japan to open trade to the West, which led to the end of the shogunate and the restoration of imperial power in 1868.

Heian-kyō (平安京; lit. "peaceful/tranquil capital") was one of several former names for the city now known as Kyoto. It was the de jure capital of Japan for over one thousand years, from 794 to 1868 with an interruption in 1180.

Emperor Kanmu established it as the capital in 794, moving the Imperial Court there from nearby Nagaoka-kyō at the recommendation of his advisor Wake no Kiyomaro and marking the beginning of the Heian period of Japanese history. According to modern scholarship, the city is thought to have been modelled after the urban planning for the Tang dynasty Chinese capital of Chang'an (modern-day Xi'an). It remained the chief political center until 1185, when the samurai Minamoto clan defeated the Taira clan in the Genpei War, moving administration of national affairs to Kamakura and establishing the Kamakura shogunate.

Nagaoka-kyō (長岡京) was the capital of Japan from 784 to 794. Its location was in Otokuni District, Yamashiro Province, corresponding to a 4.3 x 5.3 kilometer area spanning the borders of modern cities of Mukō and Nagaokakyō, Kyoto, the town of Ōyamazaki, and the Nishikyō-ku ward of the city of Kyoto. The ruins of the palace have been found in the Kaidecho neighbourhood of the city of Mukō and have been designated as a National Historic Site since 1964, with the area under protection expanded in 2016.

Kuni-kyō (恭仁京; or Kuni no miyako), was the capital of Japan between 740 and 744, whose imperial palace (恭仁宮 Kuni-kyū or Kuni no miya) was built what is now the Kamo neighborhood of the city of Kizugawa in Kyoto Prefecture. The ruins of the palace overlap with the ruins of Yamashiro Kokubun-ji (山城国分寺), and both were collectively designated as a National Historic Site of Japan in 1957, with the area under protection expanded in 2007.

Heijō-kyō (平城京; also Heizei-kyō, sometimes Nara no miyako) was the Capital of Japan during most of the Nara period, from 710 to 740 and again from 745 to 784. The imperial palace is a listed UNESCO World Heritage together with other places in the city of Nara (cf. Historic Monuments of Ancient Nara).

Empress Genmei ordered the Imperial capital moved from Fujiwara-kyō to Heijō-kyō in 708, and the move to Heijō-kyō was complete in 710. Heijō-kyō was modeled after Chang'an, the capital of Tang-dynasty China, although Heijō-kyō lacked walls. In the city, merchants and traders from China, Korea and India introduced various foreign cultures to Heijō-kyō through the Silk Road. As a result, Heijō-kyō flourished as Japan's first international and political capital, with a peak population of between 50,000 and 100,000. The overall form of the city was an irregular rectangle, and the area of the city was more than 25 km.