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From Post Roads to the Post Office Department

Foundations of the United States Postal Service

Post Offices and post routes have played significant roles in the growth of the United States. The Post Office Department developed new services that have lasted into the 21st century, helped blaze trails across the continent, and subsidized the development of new forms of transportation.

July 26, 1775

The Second Continental Congress met in May 1775 to plan for the defense of the colonies following the battles of Lexington and Concord, which sparked the American Revolution. Because the circulation of letters and intelligence was critical to their cause, Congress appointed a committee to consider “the best means of establishing posts.”

On July 26, 1775, Congress agreed to the committee’s plan, creating the position of Postmaster General and naming Benjamin Franklin to the job. The U.S. Postal Service traces its origin to that day, when Benjamin Franklin was appointed Postmaster General of the United Colonies, predecessor to the United States

Early Postal Legislation

In 1781, Congress ratified the Articles of Confederation. Article IX addressed postal issues: “The United States in Congress assembled shall also have the sole and exclusive right and power of … establishing or regulating post offices from one State to another, throughout all the United States, and exacting such postage on the papers passing through the same as may be requisite to defray the expenses of the said office …”

The Constitution and the Post Office

In June 1788, the ninth state ratified the Constitution, which gave Congress the power “To establish Post Offices and post Roads” in Article I, section 8. A year later, the Act of September 22, 1789, continued the Post Office and made the Postmaster General subject to the direction of the President. Four days later, President Washington appointed Samuel Osgood as the first Postmaster General under the Constitution. A population of almost four million was served by 75 Post Offices and about 2,400 miles of post roads.

Post Office Department

Because the Department awarded a large number of jobs and contracts, the Postmaster General’s power grew as well. President Andrew Jackson recognized the potential for patronage and, in 1829, invited William T. Barry of Kentucky to become the first Postmaster General to sit as a member of the President’s Cabinet. Barry’s predecessor, John McLean of Ohio, had been the first Postmaster General to refer to the Post Office, or General Post Office as it sometimes was called, as the Post Office Department, but the organization was not specifically established as an executive department by Congress until June 8, 1872.

As the nation grew, so did the need for postal services. The number of Post Offices increased from 75 in 1790 to 28,498 in 1860. Post roads increased from 59,473 miles at the beginning of 1819 to 84,860 by the end of 1823. By the end of 1819, a postal presence was available for citizens in 22 states, including the newest states of Illinois and Alabama. These new territories and states, as well as established communities, pressed the Post Office Department for more routes and faster delivery. The Department met these needs by expanding its service and developing faster ways to move mail.


In 1800, the speed of travel was limited by natural forces like wind, currents, or a horse’s pace. By century’s end, mail trains were crisscrossing the country with postal clerks onboard, who sorted mail in transit.

Steamboats carried mail as early as November 1808, and waterways on which they traveled were declared by Congress to be post roads in 1823. Between 1845 and 1855, the distance mail was transported by steamboat nearly doubled, from 7,625 to 14,619 miles.

Following the discovery of gold in California in 1848, westward immigration exploded. As the population grew, so did the need to connect the rest of the country through the U.S. Mail. The first overland mail route to California was established in the spring of 1851, bringing mail to Sacramento via Salt Lake City.

The first mail by Pony Express from St. Joseph to Sacramento took ten days, cutting the overland stage time via the southern route by more than half. The fastest delivery was in March 1861, when President Abraham Lincoln’s inaugural address was carried from St. Joseph to Sacramento in 7 days and 17 hours.

The Post Office Department recognized the value of railways to move mail as early as November 30, 1832. The expanded use of railroads greatly reduced transportation time. For example, in 1835, mail going from New York City to Raleigh, North Carolina, took about 94 hours. Two years later, the time had been cut nearly in half to 55 hours. By 1885, it was more than halved again to just over 19 hours.

The time-savings was due not only to increased use of the rails but also to better use — the introduction of Railway Post Offices (RPOs) in the 1860s “to make exchanges of mail, attend to delivery, and receive and forward all unpaid way letters and packages received.” When railway mail service began, the cars were equipped primarily to sort and distribute letter mail. By about 1869, other mail was being sorted. Parcel Post service, added in 1913, soon outgrew the limited space aboard trains. Terminals, established adjacent to major railroad stations, allowed parcels to be sorted then loaded into mail cars and RPOs for transport to cities and towns.

The Post Office Department’s most extraordinary role in transportation was played in the sky. The Department was intrigued with the possibility of carrying mail through the air and authorized its first experimental mail flight at an aviation meet on Long Island, New York, in 1911. In 1917, Congress appropriated $100,000 to establish experimental airmail service the next fiscal year.

The Post Office Department began scheduled airmail service between New York and Washington, D.C., May 15, 1918 — an important date in commercial aviation. During the first three months of operation, the Post Office Department used Army pilots and six Army Curtiss JN-4H “Jenny” training planes. On August 12, 1918, the Department took over all phases of airmail service, using newly hired civilian pilots and mechanics, and six specially built mail planes from the Standard Aircraft Corporation.

From Zone Codes to ZIP Codes

In May 1943, the Post Office Department began a zoning address system in 124 large cities to help employees sort the mail more efficiently. Zone codes were used in 131 cities in total. Most of the cities used the system until 1963, when the Department implemented an even further reaching plan, the Zoning Improvement Plan (ZIP) Code. ZIP Codes were implemented nationally July 1, 1963.


1847 – U.S. postage stamps issued 1863 – Free city delivery began 1873 – U.S. postal cards issued 1893 – First commemorative stamps issued 1896 – Rural free delivery began 1913 – Parcel Post began 1950 – Residential deliveries reduced to once a day 1970 – Express Mail service began experimentally

Postal Reorganization

In the mid-1960s, the Post Office Department struggled with outdated equipment, crowded facilities, underpaid workers, and an ineffective management structure. Congress, the President, and the Post Office Department moved to improve this situation. In April 1967, President Lyndon B. Johnson created the President’s Commission on Postal Organization.

The commission released its recommendations in June 1968. In 1969, President Richard M. Nixon supported the commission’s recommendations; others, including postal union leaders, opposed it.

In March 1970, more than 150,000 postal workers walked off the job to protest poor pay and working conditions. Although the strike lasted just 8 days, the unprecedented walkout galvanized postal reform negotiations.

On August 12, 1970, President Nixon signed into law the most comprehensive postal legislation since the founding of the republic, the Postal Reorganization Act. The act transformed the Post Office Department into the United States Postal Service, an independent establishment of the executive branch of the Government of the United States.

Through it all, the mission of the Postal Service has remained the same, as stated in Title 39 of the U.S. Code:

The Postal Service shall have as its basic function the obligation to provide postal services to bind the Nation together through the personal, educational, literary, and business correspondence of the people. It shall provide prompt, reliable, and efficient services to patrons in all areas and shall render postal services to all communities.

Want More Postal History?

See our 144-page illustrated book The United States Postal Service: An American History. PDF

Find more information online at https://about.usps.com/who-we-are/postal-history. Be sure to check out the historic photo galleries!

Special thanks to Jennifer Lynch, USPS Historian

Photographs courtesy of the U.S. Postal Service

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