Meiji Life Insurance Company Head Office Main Building

The Marunouchi Office Block That Changed What Counts as Heritage

The Meiji Life Insurance Company Head Office Main Building (明治生命保険相互会社本社本館, commonly called Meiji Seimeikan, 明治生命館) is an office building at Marunouchi 2-chome in Chiyoda City, Tokyo, completed in March 1934 and designated an Important Cultural Property on 29 May 1997.

The insurer settled on a new headquarters in 1928 and chose its architect by invited competition. The winning scheme came from Okada Shinichiro (1883–1932), then a professor at the Tokyo Fine Arts School, the institution that later became Tokyo University of the Arts. Ground was broken in September 1930. Okada died in 1932, well before the building was finished, and his younger brother Okada Shogoro, who had worked on the drawings from the outset, saw the project through. The Agency for Cultural Affairs credits both brothers with the design and supervision.

Three years and seven months separated the first excavation from handover.

What went up is a steel-framed reinforced concrete structure of eight storeys above ground and two below, with a rooftop penthouse, covering a building area of 3,949.4 square metres. The eaves sit roughly 31 metres up, matching the 100-shaku height limit that governed central Tokyo at the time. Every building along this stretch of the palace moat obeyed the same ceiling, which is why the district once read as a single continuous cornice line rather than a cluster of towers.

Why It Was Designated

The designation came on 29 May 1997, under registry number 02332, on the criterion of excellence in design. It made this the first building of the Showa era (1926–1989) to be listed as an Important Cultural Property. Until then the national register had effectively stopped at the Meiji and Taisho periods, and the decision reset where the line fell.

The Agency for Cultural Affairs is direct about the reasoning. Office blocks of this type went up in large numbers between the Taisho years and early Showa, so quantity was never the issue. What sets this one apart, in the agency's assessment, is the colonnaded elevation combined with the vast customer hall carried inside, and the judgement that the building represents a high point in the assimilation of Western design that Japanese architects had been pursuing since the 1870s.

Preserving it intact posed a commercial problem, since a low prewar block on land this valuable is an expensive thing to keep. Tokyo's special district planning framework provided the answer: the unused floor area was transferred to the adjacent high-rise, which let the 1934 fabric stay as built rather than being gutted behind a retained facade.

What to Look For, and How to Get Inside

Start on the moat side. A row of Corinthian columns runs the full height of five storeys, and each shaft carries entasis, the slight swelling that tapers toward the capital and corrects the eye's tendency to read a straight column as pinched at the middle. Stand close and the correction is invisible. Step back across Hibiya-dori and the columns read as upright rather than bowed, which is the whole point of the device.

The ground floor holds the former counter hall, a top-lit volume where daylight drops through a glazed roof onto marble from several quarries. On the second floor the corridor continues in marble, but the rooms off it switch to timber, a deliberate change of register between circulation and occupation.

Those second-floor rooms carry the building's other history. American forces requisitioned the premises on 12 September 1945 for the headquarters of the Far East Air Forces, and did not release them until 18 July 1956. Through to 1952 the second-floor conference room hosted the Allied Council for Japan, the advisory body to the Supreme Commander for the Allied Powers, and General MacArthur attended sessions there. The wartime metal requisition of 1941 had already stripped out elevators and decorative window grilles, so some of what visitors see today is restoration rather than original fabric.

The first and second floors are open to the public free of charge, with historical displays, an architectural model and video material, plus a smartphone-based guided tour. Opening hours run 9:30 to 19:00, last admission 18:30, closed Mondays. When a Monday falls on a public holiday the building opens and closes the following weekday instead. It also closes from 31 December to 3 January and on scheduled maintenance days, and numbers inside are capped, so a wait at the door is possible on busy afternoons. Photography rules are posted at the entrance and staff will advise on any restricted rooms.

Two other tenants share the ground floor. The Seikado Bunko Art Museum moved its exhibition galleries here from Setagaya in October 2022, showing East Asian art from a collection that includes seven National Treasures; it keeps separate hours of 10:00 to 17:00 and charges its own admission. A cafe occupies another part of the same floor.

Getting there is simple. Exit 3 of Nijubashimae Station on the Chiyoda subway line connects directly to the building. From JR Tokyo Station it is about five minutes on foot from the Marunouchi South Exit, and about the same from the International Forum Exit of Yurakucho Station. A ramp at the north entrance serves wheelchair users, and accessible toilets are on the first floor.