Sumitomo Realty & Development

The Sumitomo Group is one of the largest Japanese keiretsu, founded by Masatomo Sumitomo around 1615.

The Sumitomo Group traces its roots to a bookshop in Kyoto founded circa 1615 by a former Buddhist priest, Sumitomo Masatomo. Considered its spiritual founder, even today management of the group is guided by his "Founder's Precepts", written in the 17th century.

It was copper that made the company famous. Riemon Soga, Masatomo Sumitomo's brother-in-law, learned Western methods of copper refining. In 1590 he established a smelting business named Izumiya, literally meaning "spring shop". The advanced techniques, which Riemon perfected, allowed the extraction of silver from copper ore, something Japanese technology had not been able to accomplish yet.

The smelting and smithing business, which was begun in Kyoto, was moved to Osaka by the late 17th century. and Soga passed control of the company to his son Tomomochi who managed its transformation into a major trading house during the Edo period Sumitomo began to export copper, import silk, and provide financial services. By 1691 copper mining had been added to the portfolio.

The Meiji Restoration allowed Sumitomo to import and utilize Western machines and techniques in its mines. Sumitomo soon branched out into even more business areas entering the machine and coal industries, as well as the forestry, banking and warehousing businesses becoming a zaibatsu, or business conglomerate.

After World War II, the Japanese zaibatsu conglomerates, including Sumitomo, were dissolved by the GHQ and the Japanese government.

With the holding company dissolved, the group reformed as a keiretsu, a group of independent companies organized around The Sumitomo Bank (now Sumitomo Mitsui Banking Corporation) and bound together by cross shareholding.

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Wikipedia