Fourth president of the Mitsubishi zaibatsu. Born as the eldest son of IWASAKI Yanosuke, graduated from Cambridge University in 1905 and became vice president of Mitsubishi Goshi Kaisha (Mitsubishi Limited Partnership). He became president in 1916. Starting the following year, Mitsubishi’s divisions became independent as joint stock companies, completing the zaibatsu structure and growing Mitsubishi into Japan’s largest heavy industry group. He resisted voluntary dissolution during the dissolution of zaibatsu after World War II. He established and subsidized Seikei Gakuen, Mitsubishi Economic Institute, and the Tokyo Philharmonic Orchestra. Also famous as a haiku poet.