He was nephew to the Denzaburo Fujita, and brother-in-law to mining leader Gisuke Ayukawa. Born in Hagi, and died in Tokyo. He graduated from Tokyo Commercial School (now Hitotsubashi University) in 1885, and graduated from Keio University in 1889.
As a businessman
Through an investment from his uncle Fujita, Kuhara purchased the Hitachi Mine, formerly the Akasawa Silver Mine, in December 1905, and in two years it grew to become one of the four largest copper mines in Japan at the time. Using the success of this investment, in 1912, Kuhara founded Kuhara Trading Co., Ltd.
In 1915, copper poisoning in the area prompted Kuhara to knock down the shorter, older smoke stack in favour of a chimney 155 metres tall (the tallest chimney in the world at that time) It was built on the top of a mountain near the refinery. In this regard, Kuhara was the first to make use of the upper-layer air current.
Unfortunately for Kuhara, Japanese economy began caving in as World War I and World War II developed, and after the 1923 Great Kantō earthquake destroyed a number of his investments, he fell into debt, finally closing in 1928.
As a politician
Kuhara had, from prior to the war had been a syndicalist. He was also noted as the leader of the newly emerging Zaibatsu faction of Seiyukai (Political Friends Society). When Japan lost and the War Criminals' Trials began, he was accused by authorities of active participation in support of the February 26 Incident, which supposedly gave funds and refuge to radical militarists in the Coup d'etat.
During the Japanese War Trials, he was accused, but not tried, and released. Absolved of the charges, and joined the radicalist group Taisei Yokusankai. Kuhara acted as spokesman for the organization and was called the new "Political Messiah" the Prince Fumimaro Konoe, descended from Karuizawa Mountains for charged of political power.
The Hitachi Mine was succeeded by Gisuke Ayukawa, and taken over in 1981 by the Nippon Mining Holdings. Kuhara Trading Co., Ltd was succeeded by Nissei Limited.