Codes Before Computers. Secrecy From Rome to Radio

A hidden message can decide a battle, protect a ruler, expose a spy, or fail at the worst possible moment. From substitution systems associated with the ancient world to diplomatic ciphers, mechanical devices, wartime codebreaking, and radio interception, this book traces the long contest between concealment and discovery. It explains key methods in accessible language while keeping their political and military contexts in view.
Readers see cryptography not as a straight march toward modern mathematics, but as a recurring struggle shaped by human error, institutional rivalry, technological change, and the urgent need to trust communication.