The Mitsubishi Group traces its origins to Iwasaki Yatarō, who founded Tsukumo Shokai in 1870. In 1873, the company was renamed Mitsubishi Shokai. The name "Mitsubishi" derives from "mitsu" meaning "three" and "hishi" meaning "water caltrop" or "rhombus," referencing the crest of the Yamauchi family, who employed Iwasaki Yatarō.
Mitsubishi began as a shipping business following the Meiji Restoration, quickly diversifying into related sectors. This included coal mining to fuel its ships, shipbuilding for repair, iron mills to supply the shipbuilding, and marine insurance. Later, the firm expanded into areas like paper, steel, glass, electrical equipment, aircraft, oil, and real estate. In 1881, Mitsubishi acquired the Takashima Mine, and later Hashima Island in 1890, to secure coal supplies. Hisaya Iwasaki succeeded his uncle as president in 1894, modernizing the Nagasaki Shipyard and developing the Marunouchi business district.
Koyata Iwasaki succeeded Hisaya in 1916, overseeing significant expansion. In 1917, he funded the establishment of an optics company that later became Nikon. Mitsubishi Heavy Industries became a leader in Japanese aircraft development during this period. Koyata reorganized the group into its current form, spinning off departments into subsidiaries, many of which later became publicly traded. The company’s real estate holdings in Marunouchi were spun off in 1937 to form Mitsubishi Estate.
During World War II, Mitsubishi was a key player in Japan’s wartime economy, supplying ships, aircraft, and other arms through Mitsubishi Heavy Industries. The Mitsubishi A6M Zero fighter was the primary fighter of the Imperial Navy. Koyata Iwasaki, despite having business connections in the Anglosphere, stated that once Japan had decided to wage war against the United States and the British Empire, each member of the company ought to serve the country. Mitsubishi factories were targeted by Allied attacks, with one factory experiencing 494 worker deaths in a single week. Mitsubishi Mining was involved in the forced labour of Allied prisoners of war and people from Japan’s colonies, including 19 deaths of Chinese labourers at the Iizuka mine. In 2015, Mitsubishi Materials compensated 3,765 Chinese labourers and apologized to ex-American prisoners of war. The company was also involved in the opium trade in China during this period.
Following World War II, the Allied Occupation dissolved the Mitsubishi conglomerate. Mitsubishi Heavy Industries and Mitsubishi Chemical were split into three separate entities. Koyata Iwasaki defended his actions, asserting he had done his utmost for his country. Mitsubishi Estate was split into two companies, and in 1952, an attempted takeover by individuals linked to the yakuza was thwarted when other Mitsubishi companies purchased their shares at a high price. This incident accelerated the group’s reintegration. Mitsubishi Corporation was reformed in 1954, and the Mitsubishi Friday Club was established to foster camaraderie among executives. By 1964, Mitsubishi Heavy Industries had reemerged. The Friday Club symbolized an equal group of companies, rather than a revival of the pre-war zaibatsu structure.
In 1970, Mitsubishi companies established the Mitsubishi Foundation to commemorate the centennial anniversary of the group's founding. Mitsubishi companies also maintain individual charitable foundations. Mitsubishi pavilions have been featured at expositions in Japan since EXPO'70 in Osaka.
The Mitsubishi Group consists of around 40 independent companies without a controlling parent. Companies often hold substantial shares in each other. Twenty-nine companies participate in the Friday Conference, a monthly luncheon for senior executives. While initially criticized as potentially violating antitrust law, the Friday Conference is now officially a social function, though it continues to facilitate informal cooperation. The group’s heads of general affairs and legal departments also hold regular meetings. The group briefly engaged in television distribution in the early 1990s through an agreement with Westinghouse Broadcasting International.
The “Three Great Houses” of the Mitsubishi Group are:
MUFG Bank
Mitsubishi Corporation
Mitsubishi Heavy Industries
Ten other “major” group companies participate in coordinating meetings on a rotating basis.