About the St. Louis Old Post Office and Mullett:
The primary architect on the OPO was Alfred B. Mullett, supervising architect of the U.S. Treasury. The architectural style of the OPO is characterized as French Second Empire, which is the same style as the Louvre Museum in Paris, France. It is also referred to as the “General Grant Style,” because it was popularized during his presidential administration (1869-1877). Mullett also supervised the construction of five similar buildings in Washington, D.C., Boston, New York, Philadelphia, and Cincinnati. Only the OPO and the Washington, D.C. Executive Office Building next to the White House remain. The other four were demolished between 1936 and 1942.
The NY General Post Office moved from downtown to the Farley Building. The St. Louis General Post Office moved to this building: