The Pentagon 

US #O117 – War Department Official stamp.

On January 15, 1943, construction on the Pentagon, the world’s largest office building, was completed.

In May 1941, President Franklin Roosevelt declared a state of national emergency, three weeks after Germany launched a surprise attack on the Soviet Union.  For many, it seemed very likely that the US would soon enter the war.

US #1284 from the Prominent Americans Series.

At the time, the US War Department was growing quickly.  It included a staff of 24,000 people working in 17 different buildings throughout Washington DC.  And it was expected the number of workers would increase to 30,000 by the following year. A new building for the War Department had just been completed, but it proved too small for the amount of personnel, and would later be used by the State Department instead.

US #1289 is also from the Prominent Americans Series.

To solve the space issue, Army Chief of Staff George C. Marshall turned to General Brehon B. Somervell, head of the Army’s Construction Division.  Somervell developed plans for a building with four million square feet of office space that could hold 40,000 workers.  The building wouldn’t fit in Washington, DC, so he selected a site across the Potomac River in Virginia, just east of Arlington National Cemetery.  The site was known as Arlington Farm and had once been part of Robert E. Lee’s estate.

US #701 pictures Arlington Amphitheatre.

When Somervell’s architect began drawing up the design for the building, he had to base its shape on existing roads, which led to an asymmetrical five-sided building.  Somervell decided that the building couldn’t be more than four stories high because of the wartime need for steel and also to prevent blocking views of Washington, DC.  In the end, the design would be for a three-story building that he said could be completed within a year, and 500,000 square feet of which could be used within six months.

The House of Representatives and Senate passed legislation approving the construction in July and August, however, some began to question the building’s size and location, being so close to Arlington National Cemetery.  President Roosevelt was moved by the protests and decided that the building would be moved three-quarters of a mile south and its size reduced to no more than 2.25 million square feet. The new site, known as Hell’s Bottom, didn’t require the pentagonal shape, but time was limited, so they decided to follow the original plans for the five-sided building, though it would now be symmetrical.

US #2559i from the 1941: World at War sheet.

Construction on the Pentagon began on September 11, 1941. By December, 3,000 personnel could work there, but the construction was behind schedule.  Following the Japanese attack on Pearl Harbor and the US entrance into the war, the rush to complete the building was intensified.  By March 1942, there were 15,000 workers rushing to complete the building, working three shifts, 24 hours a day, with floodlights allowing them to work through the night.

US #900 from the 1940 National Defense issue.

Finally, on January 15, 1943, the Pentagon was completed and dedicated.  The size had grown to 6.14 million square feet and the cost had increased from $35 to $75 million.  After the war ended, many expected the building would be converted into a hospital, school, or headquarters for the Veterans Administration.  But the building would remain home to the War Department and its successor, the Department of Defense.  The Pentagon has since been added to the National Register of Historic Places and designated a National Historic Landmark.

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  1. It shows what can be done when we put our collective minds to something that is important to our well-being.

  2. Your illustration for the “War” Department official stamp is actually an “Agriculture ” Department stamp.

  3. #0117 would be the appropriate War Dept. Official stamp with the Lincoln portrait

    Errors happen. Interesting article though.

  4. The Germans attacked Russia on June 22, 1941. Therefore FDR’s emergency declaration could not have been issued three weeks after the attack in May.

  5. BTW, the actual construction of the building was supervised by BG Leslie Groves of the Army Corps of Engineers who later went onto supervise the Manhattan Project which led to the development of the A-Bomb. His civilian Director for the latter was J. Robert Oppenheimer.

  6. Those times are gone. Such a feat of construction accomplishment could absolutely not be even getoff the drawing boardvin this divided states of America. Threat of war or even war itself would not even bring this country together tor any worthwhile endeavor. Most especially defense. America has become too full of watered down weak and weakminded politically divided brainwashed majority. Matters not which political stripe. I really like to read about American history though, and always will. America’s best days are in the past.

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