“When Tokugawa Ieyasu planned his castle in Edo in 1590, he chose to build it on the high ground above the inlet that spread inland from the great bay in front of his new capital. Under his direction, Hibiya Inlet and various rivers in the vicinity of the castle were channeled so as to form canals and moats about the innermost portion of the city. Here, behind these watery barriers, the shogun’s headquarters were to rise, protect by fortified walls and water-filled moats.
“… By 1890, within 20 years of the imperial takeover of Edo, now Tokyo, the Meiji government and the military authorities required funds for the development of new establishments for their growing needs. Thus the land ‘within the moats’ was put up for sale. The Imperial Household did not have the funds to purchase the land, so the Mitsubishi, a leading mercantile and growing industrial family, were prevailed upon to acquire the vacant Marunouchi area in front of the palace grounds. Known derisively as Mitsubishi Meadow or the Gambler’s Meadow by those who did not have the foresight to buy the land, the Marunouchi was intended by the Mitsubishi for a Western-style complex of buildings in anticipation of the industrial and commercial growth they foresaw for the nation.”
– Tokyo: 29 Walks in the World’s Most Exciting City, John Martin & Phyllis Martin, 2012