Believe it or not ... your answer is right!
The Persians had the Pony Express thousands of years before the cowboy version took hoof ... King Xerxes of Persia was very demanding when it came to getting his mail ... he wanted to know what was going on in the far-flung reaches of his empire so he instituted a mail delivery service to get messages to his minions and to have his taxes delivered to his palace.
The Persians had a very impressive network of roads ... the mail carriers rode on horseback between way-stations ... each messenger would ride for one day and then pass the message to a fresh rider who would in turn ride for one day and then relay the message to a fresh rider.
Xerxes’ mail carriers had a really cool motto which they either lived up to or felt the wrath of the Great King ... “neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds” ... sound familiar? That same motto was accidentally foisted on the United States Postal Service when their central New York office, the Farley Post Office, was originally built in the early part of the last century ... one of the architects had the Persian motto engraved on the building’s pediment but when the Post Office building was recently refurbished, the Post Office Spokespod officially denied that the motto was theirs ... it seems a shame but anyone who has had any problems with their mail delivery knows painfully well that the rain, heat and gloom of night thing just doesn’t apply to anything but junk mail ... oh well, I guess my mail delivery will suffer for that jibe but I do everything online nowadays, so who cares!
Speaking of email ... I wonder if spammers have a motto? Perhaps it might be, “We’ll find you ... we’ll pester you ... we’ll send you a virus ... just try and stop us.” Ya gotta love their dedication!