The Alphabet of the Chaldeans

Prof Bill Buchanan OBE
2 min readFeb 17, 2024

The Chaldeans lived during the medieval era and who were thought to have magical powers.

One of their magic powers was the usage of the secret Alphabetum Kaldeorum and which was defined in a manuscript from 1429.

Some think the author of the alphabet was Duke Rodulf IV of Austria and whose grave contains an inscription enciphered with the Alphabetum Kaldeorum.

It was focused on Latin text, and so u and v are the same, while w is a double v, and where there is no j.

Overall, there are several version of the cipher — and where it is more difficult to perform a brute force analysis of it. It even used “Nulla” cipher letter to confuse the reader, and which could be ignored.

And, so, Bob has left a present for Alice, and used the Alphabetum Kaldeorum cipher. Can you find out where her present is?

Here is a helper:

And, here are 130 ciphers to solve:



Prof Bill Buchanan OBE

Professor of Cryptography. Serial innovator. Believer in fairness, justice & freedom. Based in Edinburgh. Old World Breaker. New World Creator. Building trust.