Groundbreaking ceremony for the State Department Extension, 1956.

Although the original portion of the building is still commonly referred to as the War Department Building, it became home to the State Department by the late 1940s. World War II spurred the growth of this department as well. However, the planned expansion was delayed until Congress allocated funds for the addition in 1955. Harley, Probst Associates, a joint venture between Harley, Ellington, and Day of Detroit and Graham, Anderson, Probst, and White of Chicago, won the contract for the design in 1956. The addition, known as the State Department Extension, was completed in 1960 and dedicated in 1961. The original building was informally called "Old State" with the addition identified as "New State".

Photo credit: State Dept.