The Post Office Department (1792–1971) was the predecessor of the
United States Postal Service, in the form of a
Cabinet department officially from 1872 to 1971. It was headed by the
Postal Service Act signed by
George Washington on February 20, 1792, established the Department. Postmaster General
John McLean, in office from 1823 to 1829, was the first to call it the Post Office Department rather than just the "Post Office." The organization received a boost in prestige when President
Andrew Jackson invited his Postmaster General,
William T. Barry, to sit as a member of the Cabinet in 1829.
Post Office Act of 1872 (17
283) elevated the Post Office Department to Cabinet status.
American Civil War (1861–1865), postal services in the
Confederate States of America were provided by the
Confederate States of America Post-office Department, headed by Postmaster General
John Henninger Reagan.
Postal Reorganization Act was signed by
Richard Nixon on August 12, 1970. It replaced the cabinet-level Post Office Department with the independent
United States Postal Service on July 1, 1971. The regulatory role of the postal services was then transferred to the
Postal Regulatory Commission.