Marunouchi

Marunouchi (丸の内) is a central commercial district of Tokyo located in Chiyoda between Tokyo Station and the Imperial Palace. The name, meaning "inside the circle", derives from its location within the palace's outer moat. It is also Tokyo's financial district and the country's three largest banks are headquartered there.

In 1590, before Tokugawa Ieyasu entered Edo Castle, the area now known as Marunouchi was an inlet of Edo Bay and had the name Hibiya. With the expansion of the castle, this inlet was filled, beginning in 1592.

A new outer moat was constructed, and the earlier moat became the inner moat. The area took the name Okuruwauchi (御曲輪内, "within the enclosure") around 1629, when Edo Castle was completed.

Daimyōs, particularly shinpan and fudai, constructed their mansions here, and with 24 such estates, the area also became known as daimyō kōji (大名小路 "daimyo alley"). The offices of the North and South Magistrates, and that of the Finance Magistrate, were also here.

Following the Meiji Restoration, Marunouchi came under control of the national government, which erected barracks and parade grounds for the army.

Those moved in 1890, and Iwasaki Yanosuke, brother of the founder (and later the second leader) of Mitsubishi, purchased the land for 1.5 million yen. As the company developed the land, it came to be known as Mitsubishi-ga-hara (the "Mitsubishi Fields").

Much of the land remains under the control of Mitsubishi Estate, and the headquarters of many companies in the Mitsubishi Group are in Marunouchi.

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