James William Marshall was a United States Postmaster General under President Ulysses S. Grant as well as a government administrator in several capacities for presidents Lincoln, Grant, and Hayes. Marshall was the third to last surviving cabinet member of the Grant Administration. He was not known for any involvement in Grant administration scandals, and his reputation remained intact. Marshall worked under Postmaster John Creswell who implemented racial integration of African Americans into the U.S. Postal System, during Reconstruction Era, led by President Grant.

The United States postmaster general (PMG) is the chief executive officer of the United States Postal Service (USPS). The PMG is responsible for managing and directing the day-to-day operations of the agency.