Monday, November 23, 2015

Intelligence operations in Switzerland - Hans von Pescatore, Captain Choynacki and General Barnwell R. Legge

In WWII Poland fought on the side of the Allies and suffered for it since it was the first country occupied by Nazi Germany. In the period 1940-45 the Polish Government in Exile and its military forces contributed to the Allied cause by taking part in multiple campaigns of war. Polish pilots fought for the RAF during the Battle of Britain, Polish troops fought in N.Africa, Italy and Western Europe and the Polish intelligence service operated in occupied Europe and even had agents inside the German High Command. 

Although it is not widely known the Polish intelligence service had spy networks operating throughout Europe and the Middle East. The Poles established their own spy networks and also cooperated with foreign agencies such as Britain’s Secret Intelligence Service and Special Operations Executive, the American Office of Strategic Services and even the Japanese intelligence service. During the war the Poles supplied roughly 80.000 reports to the British intelligence services (1), including information on the German V-weapons (V-1 cruise missile and V-2 rocket) and reports from the German High Command (though the agent ‘Knopf) (2). In occupied France the intelligence department of the Polish Army’s General Staff organized several resistance/intelligence groups tasked not only with obtaining information on the German units but also  with evacuating Polish men so they could serve in the Armed Forces (3).

Compromise of Polish codes

Poland’s role in WWII is well known, especially the success of Marian Rejewski, Henryk Zygalski and Jerzy Różycki during the 1930’s in solving the Enigma cipher machine, used by the German Armed forces. It is important to note that countries with large cryptologic staffs such as France and Britain had not managed to solve this device, in that time period.

Although the Poles were successful in the offence they neglected their defense. Their diplomatic, military attaché, resistance movement and intelligence service codes were read by the Germans during the war. Especially important for the Germans was the solution of the cipher used by Major Szczesny Choynacki, Polish deputy consul in Bern, Switzerland.

The telegrams of Major Choynacki

Choynacki regularly communicated with the Polish intelligence service in London and transmitted valuable reports from his agents/contacts in Switzerland and throughout occupied Europe. 

His cryptosystem consisted of an enciphered codebook. The codebook contained 4-figure groups and was enciphered with a version of the British Stencil Subtractor Frame. The codebreakers of the Signal Intelligence Agency of the Supreme Command of the Armed Forces - OKW/Chi (Oberkommando der Wehrmacht/Chiffrier Abteilung) were able to solve this system in late 1942-early 1943 and from then on his voluminous traffic to London was continuously decoded (4).

Details about the content of these messages are available from the postwar interrogations of German intelligence officers, specifically Willy Piert and Hans Von Pescatore (5). They were both members of the German Legation in Bern and they conducted intelligence operations against the Allied agencies and even the Swiss IS.

The decoded messages revealed that Choynacki had well placed agents numbered in the 500 series.

According to the Germans the most damaging agent was No 594, Isidore Koppelmann, a Jewish banker living in Basel. One of Choynacki’s decoded messages was used to uncover his identity.

It is up to historians to research this case further and identify the full extent of the damage caused to the Polish networks from the compromise of their communications.

The German spy in the US embassy and the messages of General Legge

Another interesting German operation, mentioned in the interrogations of Piert and Pescatore, was one directed against the US embassy in Bern, Switzerland. In 1941 the Germans were able to recruit a Swiss national who worked in the US embassy. This person, named Fuerst, had access to the office of the US military attaché General Barnwell R. Legge and he was able to take documents plus the used carbon paper and give it to the Germans. These documents revealed some of Legge’s sources:

Although Fuerst was apprehended in March 1942 the information he provided, coupled with decodes of US traffic (6), gave the Germans an insight into the sources and operations of the US intelligence agencies.


(1). Journal of U.S. Intelligence Studies article: ‘England's Poles in the Game: WWII Intelligence Cooperation’

(2). War in History article: ‘Penetrating Hitler's High Command: Anglo-Polish HUMINT, 1939-1945’

(3). ‘War Secrets in the Ether’, p230-1

(5). KV 2/1329 ‘Willy PIERT / Hans Von PESCATORE

Acknowledgments: The credit for locating the very interesting Piert/Pescatore report goes to Craig McKay, author of Major Choynacki’s Ace: the Solution to an Old Puzzle of Wartime Intelligence.

Thursday, November 19, 2015

Toivo or Karl? – To err is human vol3

In WWII the Finnish codebreakers solved the codes and ciphers of several countries. In the diplomatic field their greatest success was achieved against the State Department’s M-138-A strip cipher. One of the people who played a key role in this operation was the cryptanalyst Karl Erik Henriksson.

However there was another person working for Finnish signals intelligence named Henriksson. This was the radio operator Toivo Erik Henriksson. It seems that I mixed them up.

Thus the passage ‘Other important people were Pentti Aalto (effective head of the US section) and the experts on the M-138 strip cipher Toivo Erik Henriksson and Kalevi Loimaranta’, in The Finnish cryptologic service in WWII turns into:

Other important people were Pentti Aalto (effective head of the US section) and the experts on the M-138 strip cipher Karl Erik Henriksson and Kalevi Loimaranta

I have to thank Craig McKay for pointing out this mistake and my friends in Finland for clarifying that Toivo was a radio operator.

Thursday, November 12, 2015

C.G.McKay’s website ‘Intelligence Past’

Craig McKay, author of ‘From Information to Intrigue’, ‘Swedish Signal Intelligence’ and contributor to journals such as Intelligence and National Security, Journal of Intelligence History and Cryptologia has started a new website dealing with intelligence history. He has already added several essays on interesting cases plus he has uncovered the identity of the mysterious Polish agent 594.

If you’re interested in intelligence history you should check out his site Intelligence Past.

Q&A with Craig McKay:

Craig was kind enough to answer some of my questions.

1). How did you become interested in WWII intelligence history and what was the process that led to the publication of two books on the subject?

Part of the reason, I gave on my site, namely growing up at a time when the two great wars of the twentieth century were very much part of living memory. But why, you may still ask, study intelligence, rather than say the history of weapon development, another interesting and perhaps more important subject? I suppose the answer lies somewhere in our psyche. A clue might be the following anecdote. As an insufferable sixteen-year-old, I acquired the atrocious habit of writing down various observations in aphoristic form. One of them was: “But surely, in some sense, the perfect actor is still undiscovered.” Anybody who says something like that, is more or less fated to become interested in the
world of secret intelligence!   With regard to my books, these merely reflected my own location in Sweden. I was there, I was interested in the history of intelligence and discovered that apart from journalistic accounts, not much serious work had been done. My interest in SIGINT, cyphers and such things, however, had another origin. I had worked in the field of mathematical logic under Professor R.L.Goodstein. At that time, logic and the foundations of mathematics were peripheral subjects in the British mathematical curriculum. Computing was mainly still numerical analysis.  I recall giving a lecture on Turing machines about 1964 when few professional mathematicians in Britain had heard of his work, far less took an active interest in the subject. It sounds quite extraordinary now but so it was. Of course, no one spoke about his war work. Turing was only one of the mathematical logicians involved in wartime cypher work. There were others such as Turing 's pupil Robin Gandy, Hasenjaeger in Germany, Quine and Rosser in the US.

2). Why did you decide to start the ‘Intelligence Past’ website and what are your goals for it?  

My motivation was, I confess, entirely egotistical: to get my various bits and pieces on the history of secret intelligence out on the web rather than let them perish instantaneously with me. What other people do with them is entirely up to them. It would be nice when I am still around, if some braver souls were encouraged to post their own pieces on the site. Let’s see what happens. 

3). What areas of intelligence history do you find most interesting and what are you currently researching?

Because of my own history- virtually a lifetime in Sweden to which I remain greatly attached, I have tended  to limit my own interests in two ways (i) geostrategically I focus on Northern Europe and (ii) thematically I am also very interested in the interaction between neutrality and intelligence. About the latter, I say a bit in the first few pages of my book ‘From Information to Intrigue’. At the moment, I have been looking at old puzzles connected with Polish intelligence such as Major Choynacki`s wartime agent network.  The Poles are most extraordinary people. Their troubled history, sandwiched between Germany and Russia, has made them masters of the dark conspiratorial arts. There are naturally many other things which I think about as diligent readers of my site will discover.

4). Which unsolved cases from WWII do you think researchers should try to investigate further?

There is no shortage of questions, that’s for sure! Here’s a few straight from the top of my head.

(1) Why were the Russian organs so concerned with Raoul Wallenberg?  Lots has been written (some by me) but we are still in the dark. 

(2) Why did the Soviet authorities expel the Swedish Minister and his Military Attache during the war? Was it mere tit-for-tat for Swedish action against Soviet espionage in Sweden?  I would be interested to know if it was partly due to certain statements about these Swedish diplomats in Japanese diplomatic traffic that the Soviet Union is known to have read. The Swedish Minister (Assarsson) was a garrulous fellow who occasionally spoke to his Japanese colleague about the war situation.

(3) How far was the Abwehr involved in the Hess flight to Scotland? I have written a short paper on this but so far without being able to interest anyone else to investigate further.

(4) The MAX network in the Balkans: how one longs for a detailed Russian account of this case by a Russian historian using their own archives. Were Kauders, Hatz and Enomoto all long term Soviet assets?  Did Nahum Eitington make a special journey for a conspiratorial treff with Enomoto and Kauders in Greece in October 1940?

(5) How closely did German intelligence follow the telegram traffic of the Jewish Agency during the war?

(6) Who was the spy NERO in Spain/Portugal reporting on the UK and run by the Hungarians in the last year of the war? His name crops up in Schellenberg and Höttl testimonies.

(7) Why is there not more about the use made of COMINT in Economic Warfare during the war?

(8) What was the greatest triumph of Soviet wartime SIGINT?

A last comment: never forget that in any significant spy case there will always be loose ends.
Paradoxically that is both a limitation and an opportunity. 

Tuesday, November 10, 2015

Report on the solution and processing of the Soviet Army’s 5-figure code

The use of signals intelligence and codebreaking by the Germans and Soviets in the Eastern front is a subject that has received very little attention by historians so far. The main reason was the lack of adequate sources. The archives of the Soviet codebreaking organizations remain closed to researchers but in the last decade many important documents on German signals intelligence operations have been released to the public archives. 

From these documents it is clear that the Germans invested significant resources in their signal intelligence agencies and relied on their output during the fighting in the East. Against an opponent that outnumbered them in men and war materiel (tanks, planes, artillery) signals intelligence gave them the opportunity to monitor enemy movements and make efficient use of their limited resources.

The cryptologic systems used by the Soviet Union at low and mid level were extensively compromised during the war and in 1941-42 even their high level 5-figure code could be read. 

It seems that in 1942 a detailed report was prepared on the German exploitation of the Soviet army’s 5-figure code. The report of Area X - (Gebiet X) of April 1942, from the war diary of Inspectorate 7/VI, says:

Über die lösung, entwicklung und Bearbeitung des 5Z Materials wird demnächst ein Sonderbericht herausgegeben werden der die arbeit der Ez.- Gruppe der In 7/VI auf diesem Gebiete eingehend schildert. Dieser Sonderbericht wird den Zeitraum vom 22.6.41 (Beginn des Osteinsatzes) bis zum 22 April  1942  (Abgabe der EZ Bearbeitung an die Ez. - Gruppe des Herrn Prof. N) umfassen.

Translation by Frode Weierud:

A special report will soon be issued that will describe in detail the work of the deciphering group of In 7/IV in solving, developing and processing the Russian 5-figure code. This special report will cover the period from 22.6.41 (the start of the eastern campaign) until 22 April 1942 (handing over the processing to the deciphering group of Professor N.).

Unfortunately I have not been able to locate this file and it is not mentioned in TICOM report IF-272 which lists the files of Inspectorate 7/VI recovered in 1947 from a camp in Austria.

Sunday, November 1, 2015

Compromise of the State Department’s M-138-A strip cipher and the traffic of other US agencies

During WWII the US State Department used several cryptosystems in order to protect its radio communications from the Axis powers. The main systems used were the unenciphered Gray and Brown codebooks along with the enciphered codes A1, B1, C1, D1 and the new M-138 strip cipher. 

In the period 1940-1944 German, Japanese and Finnish codebreakers could solve State Department messages (both low and high level) from embassies around the world. The M-138-A strip cipher was the State Department’s high level system and it was used extensively during that period. Although we still don’t know the full story the information available points to a serious compromise both of the circular traffic (Washington to all embassies) and special traffic (Washington to specific embassy). In this area there was cooperation between Germany, Japan and Finland. The German success was made possible thanks to alphabet strips and key lists they received from the Japanese in 1941 and these were passed on by the Germans to their Finnish allies in 1942. The Finnish codebreakers solved several diplomatic links in that year and in 1943 started sharing their findings with the Japanese. German and Finnish codebreakers cooperated in the solution of the strips during the war, with visits of personnel to each country. The Axis codebreakers took advantage of mistakes in the use of the strip cipher by the State Department’s cipher unit.

Traffic of other US government agencies

Apart from purely diplomatic traffic the Axis powers were also able to read some of the messages of other organizations that were occasionally enciphered with State Department systems. I’ve covered the compromise of the communications of the Office of Strategic Services, the Office of War Information and the Military Intelligence Service but these were not the only agencies affected.

According to US reports from 1943 and 1944 (1), separate M-138-A alphabet strips were used by the State Department for messages of the Foreign Economic Administration, War Shipping Administration, Office of Lend-Lease Administration and the War Refugee Board.

The State Department files on the Strip Cipher (2) show that a set of strips titled 00-1 (and key table C) was introduced in late 1943 for enciphering the confidential traffic of other US government agencies. In January 1944 the sets 00-2 and 00-3 were sent to the embassies in Algiers (Free French), Turkey, Egypt, UK, Calcutta, Portugal, Spain, India, Sweden, Iran, Iraq, Beirut.

The 00-4 strips replaced set 00-3 in October 1944.

Was the traffic of these organizations also compromised? It seems so, as some German decodes of State Department traffic contain information on economic matters and Lend Lease shipments (3) and the book ‘Hitler, the Allies, and the Jews’ mentions several War Refugee Board telegrams that were decoded by the Germans (4).

Unfortunately we will have to wait for the release of more classified reports, from the NSA and the State Department, in order to assess the full extent of this compromise.


(1). NSA Friedman collection: ‘Statement of cryptographic systems now in use by Department of State’ (dated November 1943) and NARA - RG 457- Entry 9032- box 1.384, file 'JCS Ad hoc committee report on cryptographic security of government communications' (report of June 1944)

(2). New developments in the strip cipher case

(4). ‘Hitler, the Allies, and the Jews’, p200-201 - p265-267 - 287-288