Spies in the Ancient World, Part 2: On His Roman Emperor's Secret Service

History Unplugged Podcast · Jul 4, 2019 · 49m

In this episode we are looking at ancient Greek cryptography and the Roman frumentarii, a group of wheat sellers who turned into the empire's premier intelligence outfit in the second century.

In the fourth century BC, Aeneas Tacticus wrote “How to Survive Under Siege.” He goes into considerable detail on cryptography and steganography—the art of concealing a message. Methods of steganography included writing on strips of papyrus and hiding them either on the body of a person or on a horse. The strip could be hidden in a soldier’s tunic or cuirass, or under a horse’s bridle. More creative…