The Military Postal Express Service

US #493 increased in use during the war due to a change in postage rates. There are several different “Types” of 3¢ stamps due to variations in the plates.

On May 9, 1918, the US War Department created the Military Postal Express Service (MPES) to handle military mail in Europe during World War I.  It was the first postal system in the world to be created by an Army.

The US postal service delivered most soldiers letters during the Civil War.  In fact, they instituted the Soldier’s Letter Program, which allowed soldiers to send their letters without stamps, with payment being collected by the recipient.  And because of the large number of soldiers’ letters being sent home, the post office inaugurated free home delivery for cities, which led to the daily home delivery we know today. 

US #517 – Higher denomination stamps such as this were used to send heavier packages overseas during the war.

The US postal service continued to handle military mail into World War I.  Within months of America’s entrance into that conflict, civilian postal workers traveled to Europe to set up a postal service for the American Expeditionary Forces.  Back in the US, other postal workers set up the Chelsea Terminal on New York’s Hudson River to serve as the primary sorting station for military mail.  Mail heading to Europe was transported across the US via the Railway Mail Service to this terminal for processing before being sent out.

US #5300 was issued for the 100th anniversary of WWI.

The post office launched several initiatives for military mail.  This included free postage for soldiers and the creation of Army Post Office (APO) numbers, to keep troop locations private.  They also developed a flexible address system that was able to follow troop movements.  During the 11 months they operated, the post office set up 169 post offices, delivered over 35 million letters and 15 million packages to servicemen in Europe, as well as over 15 million letters to families back home. 

Despite the success of this undertaking, the post office and military had some issues with their arrangement.  Largely, it was the War Department’s hesitance to release troop locations.  So on May 9, 1918, the War Department issued General Order No. 72, assuming control of military mail and establishing the Military Postal Express Service (MPES). 

The MPES continued to use many of the systems established by the post office, and even hired some of their postal agents and commissioned them as officers.  The MPES had both stationary and mobile post offices.  The mobile units moved with the troops and the men received mail with their daily rations.  When the soldiers moved, the new location wasn’t revealed to the mail distribution centers until the camp was set up.

US #5300 – First Day Cover with Digital Color Postmark.

To prevent military information from being disclosed, the MPES began censoring the mail.  Anything pertaining to future operations was crossed out.  This included casualties, condition and morale of the troops, and condition of equipment.  Though the men at the front understood the need for this precaution, many people in the US didn’t want their letters read by the postal service.

US #537 was issued to celebrate the end of WWI.

President Wilson was asked to decide whether it was necessary to censor all the mail.  His conclusion was, “I think that a time of war must be regarded as wholly exceptional and that it is legitimate to regard things which would in ordinary circumstances be innocent as very dangerous to the public welfare…”  So, the censorship continued.

The MPES remained in service well after the war ended, closing its last outpost on January 31, 1924.  The military continued to handle its own mail in the wars to come and today provides this service through the US Military Postal Service (MPS).

Click here to find lots of stamps honoring World War I.  And here for more WWI-era Washington-Franklins.

Click here to see what else happened on This Day in History.

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  1. My experience with having been in the military, being an “army brat” (and proud of it), and having a son and a grandson who have or are now serving, is that censorship only existed in times of war. No letters I ever sent or received have ever been censored.

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