This building was constructed in 1920 as the Shimonoseki Branch Office of Mitsui Bank, which expanded to the Kanmon region. It was designed by Uheiji Nagano who is famous as a master of bank architecture. The building is in a corner of the former bank district that was a symbol of Shimonoseki’s success. The exterior is completely bilaterally symmetrical with a Renaissance theme. It is a true classical architectural structure that has carvings and decorations on the facade covered in granite. Inside, there is a spacious atrium, but no pillars. A Kahn-style reinforced concrete construction, a structural type developed in the United States, was used to create expansive space. Uheiji Nagano, who was in charge of design, was an architect known as the apprentice to Tatsuno Kingo who worked on Tokyo Station. He made a name for himself designing a number of bank structures. In 1897, he became an engineer for the Bank of Japan, and under construction advice from Tatsuno Kingo, he was involved in supervising designs for branch offices in places including Osaka, Kyoto, Nagoya, and Otaru among other places. After his design was chosen in a 1909 design competition for the Taiwan Government-General Office Building, the first competition in Japan, he temporarilywas engaged in temporarily workeding for the Taiwan Government General. After establishing a design office in 1913, he was involved in numerous classical architectural structures, such as the Shimonoseki Branch Office of Yokohama Specie Bank and the Okayama Branch Office of the Bank of Japan. In 1917, he was chosen as the first chairman of the Nihon Kenchikushi Kai (Japan Architects Association; later, Japan Institute of Architects ). Mitsui Bank transferred business rights to Hyakuju Bank in 1933. This building became the head office of Hyakuju Bank. After Yamaguchi Bank was founded through the merger of 5 banks in the prefecture in 1944, it was used as the head office of Yamaguchi Bank. After the current head office was completed in 1965, it became the Kannonzaki Branch Office of Yamaguchi Bank, and after the Kannonzaki Branch Office became the Irie Branch Office in 1969, the building was used for in-house bank meetings and gatherings as a Yamaguchi Bank annex until 2004. In fact, Mitsui Bank had at one time withdrawn from Shimonoseki prior to the construction of the branch office. When the establishment of private banks was permitted in 1876, Mitsui Bank opened a first-class satellite office for commodities wholesalers in Shimonoseki. In 1893, the satellite office was upgraded to a branch office and business expanded. However, commodities wholesalers subsequently declined. The Shimonoseki Branch Office closed in 1907 and the business was transferred to Hyakuju Bank. Business in the Kanmon region was centered in Moji. In time, WWI broke out and Japan’s economic climate improved with the breakout of WWI. Trade in Shimonoseki also greatly developedexpanded, and a satellite office was once again opened in 1916. The satellite office was upgraded to a branch office in 1918, and in 1920 a new place of business was built.