Office of the Historian

U.S. Diplomatic Couriers

In 1918, the Diplomatic Courier Service was established to support the work of U.S. diplomats by ensuring that classified messages and materials were delivered safely and securely to U.S. embassies and consulates around the world. In the 1950s, before the onset of the jet age, this small group of couriers traveled tens of thousands of miles per year, often spending months on the road.

In the words of the couriers themselves, this documentary series chronicles three of the trips they made: Through the Khyber Pass, Behind the Iron Curtain, and Into Moscow. A fourth documentary, Before the Jet Age, describes the Diplomatic Courier Service itself during this era.

2018 Centennial of the U.S. Diplomatic Couriers

The Diplomatic Courier Service marks its 100th anniversary in 2018. For more information about the history of the Diplomatic Courier Service, as well as the Department’s modern service, visit the links below:

Diplomatic Immunity and the Vienna Convention on Diplomatic Relations

Over the years, Diplomatic Couriers have been protected by official diplomatic passports, letters of passage signed by the Secretary of State, and even foreign-issued diplomatic passes.

Since 1961, official diplomatic correspondence has been protected under Article 27 of the Vienna Convention on Diplomatic Relations. The Vienna Convention underscores that official messages are inviolable, diplomatic bags cannot be opened or detained, and diplomatic couriers are “not liable to any form of arrest or detention.”  The Vienna Convention built on earlier efforts to codify diplomatic roles and immunities, most notably the Congress of Vienna in 1815 and the Havana Convention on Diplomatic Officers in 1928.

More Information

For information on the U.S. Department of State and U.S. diplomacy during this time, visit Containment and Cold War, 1945–1961.