Secret code of Augustus?

[Epictetus]

Seutonius says that Augustus had a rather simple method for writing secret messages:

Whenever he wrote in cipher, he wrote B for A, C for B, and the rest of the letters on the same principle, using AA for X.

Augustus, 88

According to Seutonius this is the same method Caesar used:

There are also letters of his to Cicero, as well as to his intimates on private affairs, and in the latter, if he had anything confidential to say, he wrote it in cipher, that is, by so changing the order of the letters of the alphabet, that not a word could be made out. If anyone wishes to decipher these, and get at their meaning, he must substitute the fourth letter of the alphabet, namely D, for A, and so with the others.

Caesar, 56.6

Several weeks ago I was watching a documentary on television that claimed Augustus had another method that involved using the start of the Iliad (I think) as some sort of cipher code. Now I don’t remember exactly what the documentary said, but I’ve seen this mentioned on other websites, including for a cryptography class in a university in New York State, so I must not have dreamed it.

But the problem is I’ve been vainly trying to find out the source for this information, to no avail. Has anyone ever heard of another type of cipher used by Augustus besides that which Seutonius mentions?

[D B Campbell]

Has anyone ever heard of another type of cipher used by Augustus besides that which Seutonius mentions?

I believe I came across this in a book about computer programming -- I cannot now locate it -- but it seems highly unlikely that the Romans had such a book cipher, which is rather more sophisticated than the simple "Caesar cipher".

I wonder if modern cryptographers have simply dubbed it an "Augustus" cipher, because it is one stage better than a "Caesar" cipher?

[Perdiccas]

Recalling from my class of cryptography a Vigenere Cipher seems more likely, simply because you can encrypt every word, not only words from the given text passage. But I don't remeber if there was any mention of this kind of cipher being used earlier than the medieval. The cipher itself is not much more complicated than a simple Caesar cipher.

[D B Campbell]

Of course, it may be confusion with the wrong Augustus (Augustus, Duke of Brunswick, author of Cryptomenytices et Cryptographiae libri IX, 1624)?

[Epictetus]

Thanks for the replies.

I wonder if modern cryptographers have simply dubbed it an "Augustus" cipher, because it is one stage better than a "Caesar" cipher?

Yes, I'm beginning to think it might be a naming issue of some sort.

[Sean Manning]

I haven't heard of this one either.

Book ciphers tend to rely on a standardized text with numbered lines and pages, which was hard to find in antiquity. Using the start of a book of Homer for one might have worked, but I'm still skeptical. Duncan's idea that this German duke was confused with the emperor sounds possible.

[Casmin]

"When Augustus wrote in cypher he simply substituted the next letter of the alphabet for the one required, except that he wrote AA for X."

Suetonius The Twelve Caesars. Chapter II verse 88

Edit: Ah I should pay better attention. This was already said

[M. Demetrius]

Well, Casmin, if you would feel better, I could say it again...that's usually my job, but thank you for filling in for me. :lol: :roll: