On February 20th, 1792 – President George Washington signed the Postal Service Act creating the Post Office Department. Postmaster General John McLean was the first to call it the Post Office Department rather than just the “Post Office.” The organization received a boost of prestige when President Andrew Jackson invited his Postmaster General, William T. Barry, to sit as a member of the Cabinet in 1829. The Post Office Act of 1872 elevated the Post Office Department to Cabinet status.
On August 12, 1970, President Richard Nixon signed the Postal Reorganization Act that led to the replacement of the cabinet-level Post Office Department to the independent Postal Service on July 1, 1971.
While February 20th marks the official birth of the USPS, its roots can actually be traced back to 1775 during the Second Continental Congress, where Benjamin Franklin appointed the very first postmaster general.