Koyata Iwasaki

Koyata Iwasaki was a Japanese businessman born in 1879 in Tokyo. He was the eldest son of Yanosuke Iwasaki, who served as the second president of Mitsubishi, and Sanae Goto, daughter of Shojiro Goto. Iwasaki received education at the First Higher School and subsequently attended Tokyo Imperial University. He later studied abroad at Pembroke College, Cambridge University, where he studied history, geography, and sociology.

In 1906, Iwasaki began his professional career with Mitsubishi. That same year, he married Takako Shimazu, the daughter of Baron Uzuhiko Shimazu. Following the death of his father in 1908, he inherited the family barony, becoming Baron Koyata Iwasaki.

In 1916, Iwasaki succeeded his cousin Kyuya Iwasaki as the President of Mitsubishi. His tenure lasted until 1945, totaling 29 years. During his leadership, he expanded Mitsubishi’s operations by establishing subsidiaries across various sectors, including mining, shipbuilding, banking, trading, and real estate. These subsidiaries often enjoyed dominant market positions, functioning as de facto monopolies or oligopolies. To facilitate growth, he sold approximately half of each subsidiary’s shares to the public, while Mitsubishi’s headquarters retained ownership of the remainder. In addition, Iwasaki privately funded the creation of an optics company in 1917, becoming its majority shareholder; this company later developed into Nikon.

Koyata Iwasaki was opposed to the dissolution of zaibatsu ordered by the Allied Occupation Forces following Japan's defeat in World War II in 1945. The order mandated the breakup of major industrial conglomerates and required members of their founding families to divest their shares. Iwasaki strongly objected to this process, but he died in December 1945, shortly after the order was issued. His residence in Roppongi was later replaced by the International House of Japan. Although the original building was reconstructed in 1955, much of the garden commissioned by Iwasaki in 1930 remains largely unchanged.

Iwasaki’s estate included Atami Yowado, a holiday villa located in Atami, Shizuoka Prefecture. The villa’s garden was designed in a grand style by Ogawa Jihei VII, a notable garden architect from Kyoto. In 1978, the Mitsubishi Kinyokai, comprising 29 core companies of the Mitsubishi Group, established a management committee for Atami Yowado. Today, the villa functions as a club for Mitsubishi executives.