Former Ministry of Finance Building (Current MOF Headquarters)

The former Ministry of Finance Building (旧大蔵省庁舎), now the Ministry of Finance Headquarters (財務省本庁舎), stands at 3-1-1 Kasumigaseki, Chiyoda Ward, Tokyo — the heart of Japan's central government district. This imposing five-story reinforced concrete structure with one basement level (total floor area approximately 56,305 square meters) is one of the most historically significant surviving government buildings from wartime Japan.

CONSTRUCTION AND DESIGN

The building was designed by Okuma Yoshikuni (大熊喜邦), chief architect of the Ministry of Finance Construction and Property Management Bureau (大蔵省営繕管財局). Construction commenced in 1934 (Showa 9) as part of the ambitious Showa-era central government district development plan for Kasumigaseki. The site had previously been the Honjo residence of the former Miyazu domain (宮津藩本荘邸). Okura Civil Engineering (大倉土木) began work in 1936, but the outbreak of the Second Sino-Japanese War in 1937 caused severe material shortages, forcing a temporary halt. Work resumed in 1939 under Inoue Construction (井上工業). The building reached provisional completion in 1940 (Showa 15) but with numerous defects; official completion came in 1943 (Showa 18), though exterior tile cladding remained unfinished due to wartime material rationing.

The design is predominantly utilitarian and austere, reflecting wartime austerity. The notable exception is the entrance portico featuring a distinctive triple-arch motif (3連アーチ). The interior preserves a grand spiral staircase with red velvet carpeting reminiscent of Meiji-era aesthetics. A traditional well stone inscribed "Kiyotaki Water" (清瀧水), believed to originate from the former Honjo residence, remains in the front courtyard.

WARTIME ROLE AS ECONOMIC CONTROL CENTER

During the war years, the Ministry of Finance (大蔵省) was the linchpin of Japan's wartime economic mobilization. Following the enactment of the National Mobilization Law (国家総動員法) in April 1938, the ministry exercised sweeping control over government finances, war bonds, taxation, currency, and the allocation of capital to war industries. Working in coordination with the Planning Board (企画院) and, after 1943, the newly established Munitions Ministry (軍需省), the Finance Ministry directed the economic resources of the empire toward total war.

Key wartime economic policies administered from this building included: management of wartime special accounts and military expenditures that consumed over 70% of the national budget; direction of the financial controls system under the "three fiscal and economic principles" announced by Finance Minister Kaya Okinori in 1937 (production expansion, material supply adjustment, and international payment balance); oversight of the wartime tax system that squeezed the civilian economy; and coordination of war bond campaigns that extracted savings from the population.

SURVIVING THE AIR RAIDS

The building's reinforced concrete construction proved critical during the devastating U.S. air raids on Tokyo in 1945. The Kasumigaseki government district was targeted multiple times, and many structures in the vicinity were destroyed — including the German Embassy in nearby Nagatachō. However, the Finance Ministry building, along with the Interior Ministry (人事院) and Education Ministry buildings, survived; this is commonly attributed to their reinforced concrete construction and protective roof layers, which provided fire resistance against incendiary bombs. The building's exterior walls, though damaged, remained structurally sound and were retained for postwar reconstruction.

OCCUPATION AND POSTWAR RESTORATION

Following Japan's surrender on August 15, 1945, the building was immediately requisitioned by the Supreme Commander for the Allied Powers (SCAP/GHQ). It served as U.S. military offices and barracks for a full decade, during which the Finance Ministry was forced to operate from a temporary location in a primary school building in Yotsuya (四谷). The building was returned to Japanese control in 1955 (Showa 30). Comprehensive renovation then began, including completion of the long-delayed exterior tile cladding and repair of war damage. All restoration work concluded in 1963 (Showa 38) — twenty years after the original completion date.

MODERN ERA

The building continues to serve as the headquarters of both the Ministry of Finance (財務省) and the National Tax Agency (国税庁). Between 2015 and 2020, it underwent a major base-isolation seismic retrofitting project, significantly enhancing earthquake resistance while preserving the original structural framework. The building now meets modern disaster-response facility standards essential for government continuity.