The motto of the U.S. Diplomatic Courier Service — “None swifter than these” — is taken from Greek historian Herodotus’ description of the mounted messenger service used by the king of Persia in 430 BC.
The Diplomatic Courier Service traces its origin to 1918, when the U.S. Army established its “Silver Greyhounds” courier unit.


In March of that year, U.S. Army Gen. John Pershing authorized U.S. Army Major Amos J. Peaslee (shown left) to organize a military courier service, the “Silver Greyhounds”, to carry sensitive correspondence between Paris and Washington during World War I and during the U.S.-led peace conference that followed.
Within three weeks, transit times for U.S. correspondence between Paris and Washington dropped from roughly five weeks to less than two weeks.
In November 1918, the Silver Greyhounds’ consignments shifted from being primarily military to being primarily diplomatic. Thus, the Silver Greyhounds became the first U.S. organization dedicated specifically to the movement of diplomatic pouches.
In December 1918, the Silver Greyhounds formally began to support the State Department in advance of the Paris Peace Conference delegation in early 1919.
In 1985, the Diplomatic Courier Service became part of the Diplomatic Security Service during a State Department consolidation that included the creation of the Bureau of Diplomatic Security and DSS.