APO and Military Mail History

Beginning with the Civil War, organizing soldiers’ mail has been a tedious and continuous project for the Postal Service and military.

Without Postal Inspectors’ assistance creating the APO system and supporting operations during war time, mailing letters to and from soldiers would not be as fluid as it is today.

The Civil War and the Spanish-American War

During both the Civil War and the Spanish-American War, United States Post Office Department workers delivered nearly all mail to soldiers and their families. Often, mail would be transported be trusted soldiers in moving units, then sorted and distributed by postal employees.

D.B. Parker was a great example of how this process worked during the Civil War. Moving with his unit, Parker's main goal was ensuring the safe delivery of mail to soldiers. Due to many soldiers' inability to pay for postage during the Civil War, the Post Office Department created the predecessor for the modern "free mail." Called the "Soldier's Letter" program, it allowed soldiers to send letters without stamps, and payment was collected from the recipient.

The United States Postal Service and Inspection Service continued to handle all military mail until World War I.

WWI and Developing APOs

At the beginning of WWI, military personnel had little to do with mail services. The Railway mail Service (RMS), operated by civilian postal employees, transported mail across the country Mail was then carried on civilian ships and collected again by RMS workers and distributed. In 1918, Brigadier General Robert C. Davis oversaw the expansion of operations in European Theatre, including the initial responsibility of overseas Post Offices.

The Military Postal Express Service (MPES) was developed as the first all-military mail service. Initially, five APOs (Army Post Offices) were established in France, until the arrival of Postal Inspector William Kenyon, who helped establish at least 30 more around France and Germany.

At the end of WWI, as troops were demobilizing, mail delivery service was often conducted by foreign postal facilities during the 1920s and 1930s.

APO and FPO System from WWII - Present Day

APOs were assigned numbers, typically based on the infantry unit or geographical location. Soldiers' mail was delivered to the nearest APO and then distributed. During WWII, all mail transportation was done separately and no longer used moving troops to carry mail.

During WWII, Postal inspectors around the nation were frequently drafted. While some went into infantry, many were assigned to military postal units to ensure successful mail delivery.

The Korean and Vietnam Wars saw upwards of 11 tons of mail sent to troops daily. The APO system remained largely the same, but the Postal Service had a far greater role stateside. They transported all mail to the West Coast and then distributed it to the Pacific Theatre APOs and Fleet Post Offices (FPOs) that served Navy personnel.

Today, the military postal system still follows the format create during the First World War. While minor system adjustments may be made, depending on the location of conflicts, the APO/FPO system remains a successful venture for military mail.


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