Saturday, May 25, 2019

Histocrypt 2019 program

The program for the International Conference on Historical Cryptology 2019 has been posted.

For me the more interesting presentations (based on the titles) are:

4. Eugen Antal, Pavol Zajac and Otokar Grošek: Cryptology in the Slovak State During WWII
5. Dermot Turing: The Typex Scare of 1943
6. George Lasry: A Practical Meet-in-the-Middle Attack on SIGABA

I hope they post their proceedings at their site like last year.

Sunday, May 19, 2019


In the essays French Hagelin cipher machines and The French War Ministry’s FLD code I added information from the Bulletin de l’ARCSIarticles  Essai d'historique du Chiffre’. Specifically in the paragraphs ‘French Army codes and ciphers’ and ‘French military codes and the Battle of France’.

Thursday, May 9, 2019

Saturday, March 23, 2019


In Compromise of State Department communications in WWII I made the following correction. I had written that the M-325 SIGFOY cipher machine was introduced into service in the second half of 1944, however that was not correct.

According to NARA - RG 59 - Purport Lists for the Department of State Decimal File 1910-1944 – microfilm 611 - 119.25 MC-325 the device was distributed to foreign posts in the second half of 1944 but the keylists were for the period January-June 1945. Thus the device could not have been used in 1944 by the State Department.

Wednesday, March 6, 2019

Information on State Department codes and ciphers

NARA has uploaded the microfilms containing entries on WWII era State Department codes and ciphers.

The entries dealing with cryptology are the 119.25.

Wednesday, February 27, 2019

The missing NAAst 5 reports

Although I’ve given up on getting these files (for reasons that have already been mentioned) I will post this information in the hope that someone else will succeed.

At the US national archives, in the NSA transfer group TR-0457-2016-0017, box 45, folder 3953 there is a file titled ‘KOMMANDEUR DER NACHRICHTEN AUFKLARUNG 5, 1944 (S-013,494)’.

It is possible that this file contains the missing NAASt5 reports. Maybe someone can get hold of this file and solve the mystery.  

Tuesday, February 12, 2019

HistoCrypt 2019

Information on this year's International Conference on Historical Cryptology:

The International Conference on Historical Cryptology (HistoCrypt) is an annual conference on historical cryptology. The 2019 edition will be held from June 23-26, 2019 in the Mundaneum, Mons, Belgium.


HistoCrypt addresses all aspects of historical cryptography and cryptanalysis. The conference's subjects include, but are not limited to:

the use of cryptography in military, diplomacy, business, and other areas

analysis of historical ciphers with the help of modern computerized methods

unsolved historical cryptograms, including the Voynich Manuscript

the Enigma and other encryption machines

the history of modern (computer-based) cryptography

linguistic aspects of cryptography

the influence of cryptography on the course of history

teaching and promoting cryptography in schools, universities, and the public

Participation in the conference is mandatory for at least one author of each accepted paper. 

Submissions from those who are new to the field, particularly students, are very welcome.

We are looking forward to seeing you in Mons, Belgium

The Organizing Committee of HistoCrypt 2019