News Article

Director GCHQ commemorates crucial pre-war Enigma information-sharing meeting in Poland

Last Updated: 21 Jul 2016
Sir Iain Lobban attends a ceremony in Warsaw on Thursday 3 July 2014 to commemorate the 75th anniversary of a  meeting in Poland between Polish, French and British cryptanalysts where information was shared that proved crucial in unlocking the secret of the German military's Enigma cipher.

News article - 4 Jul 2014

Sir Iain Lobban honours those who changed history in 1939

At the event, Sir Iain delivered a speech outlining the lessons that could be learnt from that history-changing meeting that took place in Pyry Forest, near Warsaw, seventy-five years ago:

'Chief of Staff; Deputy Foreign Minister; General Hunia; Director Pailloux; Professor Zukowski, Chairman of the World Association of the Home Army; Mrs Bryschak, representing the families of the cryptanalysts; Ambassadors, Ladies and Gentlemen.

'We have come here today because seventy-five years ago General Hunia’s, Monsieur Pailloux’s, and my predecessor came here.  What happened here in 1939 changed the course of history and we are here to honour those who were responsible.  That meeting has achieved a mythical status, and I want to unpick the different strands of the myth to suggest that, far from what happened here in 1939 being a simple transactional process, there are enduring lessons for today in what led to the meeting and how relationships developed subsequently.

'The simple fact that Polish, French and British cryptanalysts met here seventy-five years ago is remarkable.  Each of the three countries had thought about processing Enigma in a different manner, with the result that at an earlier meeting, in January 1939, no real information was exchanged. 


Enigma keys close up


'From the time Enigma became known in 1926, the UK had simply treated its cryptanalysis in the same way as it handled all new cryptanalytical problems:  it was given to a single cryptanalyst for him to devise a solution.  The cryptanalyst was Dilly Knox, and he had success against the commercial variant of Enigma using paper-based techniques analogous to those he had been using against codebooks since 1914: in this case he made rods out of cardboard to simulate the way rotors would line up against each other.  Although proud of Knox’s technique, and the success it brought in dealing with the use of Enigma by General Franco and his supporters in the Spanish Civil War, the UK was actually in a cryptanalytic cul-de-sac: Knox’s method would not scale up, nor could it cope with the improvements the German military made to the Enigmas they used themselves.

'France, typically, had attacked the problem of Enigma with flair, with élan, with panache: the solution of Major Bertrand of the Deuxième Bureau was to recruit a German agent, and pay him to pass to the French copies of Enigma handbooks and key material.  France supplied this material in a collaborative venture with Poland.

'But Poland was the first of the three countries to realise that the solution of electromechanical encryption would best be carried out by mathematicians.  As early as 1928 the Polish Cipher Bureau of the General Staff had organised a course in cryptography in Poznań for maths graduates who spoke German.  A team led by Marian Rejewski worked out the wirings of the German Army Enigma rotors and had some early success by building replica Enigma machines and using their mathematical understanding to break most German Army messages.  But the Germans continued to improve the secure use of Enigma, leading the Polish Siginters again to be the first of the three countries to mechanise cryptanalysis by designing and building a machine which emulated the way Enigma machines worked.  Eventually, however, even this marriage of mathematics and engineering proved unable to cope with the increased complexities introduced by the Germans.

'The French had the foresight to see that Enigma would only be solved if the three countries met and shared knowledge, but the first meeting, in Paris, in January 1939, was a failure as neither the British nor the Poles were prepared to say what they knew.  But after the 31 March statement by the British and French Governments that they would intervene to protect Polish independence in the event of German invasion, a meeting was held here on 15 and 16 July at which the Poles shared all the progress they had made, which included information about the one variable that the British had not solved, and which would enable them to start to make progress again.


Enigma Keys


'The second strand of the story is about what happened next.  After the German invasion of Poland, the Polish cryptanalysts moved to France and operated in a joint unit with their Deuxième Bureau colleagues, linked by teleprinter to Bletchley Park, where British Sigint had moved to for the duration of the war.

'After the 1940 Armistice, the joint unit moved to the south of France where they continued to work clandestinely, and even maintain a degree of connectivity with the UK, ironically using altered Enigma machines.  After the German occupation of the Vichy zone in 1943, the unit broke up: some of the Poles were captured, the rest made their way to the UK and to the Polish Sigint unit operating there.

'The UK had asked that the Polish cryptanalysts should come to the UK after their evacuation from Poland, and again at the time of the Fall of France, but it was not to be, although some French cryptanalysts came to Bletchley Park in April 1940 and remained there until the end of the war. 

'After the war, the need to keep the story of Enigma cryptanalysis secret meant that the story of the three partners working together faded from memory, so much so that when the first volume of the Official History of British Intelligence was published in 1979 the value of the Polish and French contribution was understated – it took nine years to put it right.

'The next strand I want to unpick is about how un-nuanced the myth has become.  The story usually told is one in which the three partners are depersonalised and stand as one-dimensional types, rather than as people: they are portrayed as reluctant allies, and to a great extent competitors rather than allies.  But the way in which Major Bertrand shared the key material with the Poles, or the way in which Marian Rejewski shared his insights with Alan Turing in January 1940, are suggestive to me of a relay race in which the baton is passed between different team members, but it is the team as a whole which wins the medal.  This should be a rich story about cooperation, not about whether one partner deserves more honour than another.

'And finally, what if: what if all of the French and Polish cryptanalysts had come to Bletchley Park in 1940?  What if the responsible French, Polish and British authorities had raised themselves above the tactical noise and had thought strategically about Sigint as a combined activity?  I will return to this, but will first remind you that cryptanalysis is not the whole of the story of our joint endeavour during the Second World War.  A Polish military intercept site was established outside London and was fully integrated with the British Army’s network of stations.  It was this station which maintained its coverage of the Soviet Union after UK stations dropped theirs, and whose technical knowledge enabled UK stations to begin to cover the Soviet military after the Soviet Union became a target again.

'So far, I’ve been looking back at what happened in the past.  In what way is it relevant today?

'The first, obvious, way is that since 1939 we have never tried to do Sigint in isolation.  As far as the UK is concerned, our best known partnership is with the United States, but we also have bilateral relationships with many other countries, and, through NATO and other coalitions, a range of multilateral partnerships: all of our activities in Afghanistan in the last few years have been supported by a multinational Sigint partnership. At a deeper level, it is important to remember that these partnerships are authorised by our respective governments.  In our democratic societies, it is the elected government which determines what activities we are authorised to carry out, what relationships we are authorised to develop.

'These relationships work, because they are personal as well as organisational relationships.  It is well known that the senior British cryptanalyst here 75 years ago, Dilly Knox, threw a tantrum after learning that the Poles had solved the variable which he had failed to do: less well known is the fact that he personally bought gifts to present to the Polish cryptanalysts; or that my predecessor of the day, learning that the daughter of Colonel Mayer, the Head of the Intelligence Department of the Polish General Staff was learning English, proposed that she should exchange visits with his own daughter. On behalf of the joint French and Polish team, Major Bertrand promised the UK that the secret of success of cryptanalysis against Enigma would not be betrayed to the Germans, and it wasn’t, even though Bertrand himself, and, separately, Colonel Langer, the Head of the Polish Cipher Bureau, and four other Polish cryptanalysts were captured and interrogated.

'What happened here 75 years ago was momentous.  The UK’s Sigint Agency was able to meet the challenge posed by German cryptography in WWII simply because France and Poland were prepared to share what they knew about Enigma, and because the meeting marked the start of a collaborative process which lasted another three years, in spite of German military successes. 


Enigma Wheel


'If the French and Polish cryptanalysts had come to the UK in June 1940, what might we have achieved together?  There is of course no way of knowing, but we do know that a predisposition to international cooperation was born here seventy-five years ago.  It continued with the proposal to have a combined Anglo-French naval section at Bletchley Park, (and five Free French Siginters continued to work at Bletchley after the fall of France), with the subsequent arrival of the Americans and shows itself today in our support to coalitions.

'We are not enslaved by the past: today’s adversaries are different from yesterday’s and use a range of capabilities that the people who came here in 1939 could not have dreamt of.  But we mine the past so that we can learn from their mindset: they were faced with the greatest of challenges, and by overcoming their habit of not sharing their knowledge, they learned not just the point their new colleagues had reached, but how they had done it.

'As I end, let me return to the events of July 1939. The UK sent a party of two cryptanalysts, and a Royal Naval Direction Finding expert who wanted to discuss the creation of a joint network between the three countries.  The two cryptanalysts travelled by train—my predecessor wanted to see Germany for the last time—and at Bletchley Park his passport is on display, showing the visa granted to him by the German Embassy in London allowing him to transit Germany to get to Poland. 

'Knox’s tantrum is well-known: he could not believe that the variable he had not solved could have been a simple alphabetical order but he ended the conference, arm in arm with one of the French representatives, suitably fortified by some Polish beer, chanting "nous marchons ensembles"—not something you will see from me later on, I assure you.

'The respect and friendship that grew up between the three Sigint heads at this meeting was matched by the warm relationship which grew up between Knox and Marian Rejewski, and on his return to the UK, Knox immediately arranged for Alan Turing—who was still not officially a member of the British Sigint organisation—to meet him so that he could hear the story of what the Polish mathematicians had achieved.

'Ladies and gentleman: we really are standing on the shoulders of giants.  Let us never again forget that Sigint agencies achieve more in partnership than in isolation, that none of us has a monopoly of good ideas, and that at the heart of all of our relationships is the mutual trust and respect which we have for each other as individuals.

'I carry with me the warmest best wishes from the British Secretary of State for Foreign and Commonwealth Affairs, William Hague, who unfortunately has had to postpone his own trip to Poland; and also those of Sir John Scarlett, former Head of MI6, and now the Chairman of the Bletchley Park Trust.'

HRH The Prince of Wales sends his support

His Royal Highness The Prince of Wales sent his words of support to the ceremony marking this important event. He said:

'I am delighted to send you all my very best wishes for this important evening, commemorating, as it does, such a startling success from the collaboration between the signals intelligence agencies of our three countries, some three quarters of a century ago. I need hardly say how immensely proud I am of my position as Royal Patron of the British intelligence agencies, including Government Communications Headquarters. 

'I know the story of cooperation between Britain, France and Poland in 1939 was a truly remarkable one, and contributed enormously to the ultimate success in the fight for freedom seventy-five years ago.  As we face today's security challenges, may we work together as well as our predecessors did.

'This message comes with my very special thoughts and regards to all who work so hard to protect our freedom in the United Kingdom, France and Poland.'


Enigma x3

Background to the Pyry Forest meeting

On 25 and 26 July 1939, Polish, French and British cryptanalysts met outside Warsaw to share what they knew about Enigma.  The UK was represented by Alastair Denniston, the Head of the Government Code and Cypher School (GC&CS — GCHQ’s name until 1946) and Dilly Knox, the cryptanalyst who had led work on breaking traffic encrypted on Enigma.

At an earlier meeting in Paris in January 1939, the British and Polish sides had not been prepared to share information fully, but in July the situation was very different: the British and French governments had given formal undertakings to support Poland if it were invaded and in return, on the cryptanalytic side the Poles were prepared to explain the progress they had made against Enigma.

Even though Polish success against Enigma had been much reduced in the preceding months by measures taken by the Germans to increase Enigma security, the British and French representatives learned that the Poles were much further forward than they were, both quantitatively, in terms of the amount of material the Poles had already read, and qualitatively, in terms of the Polish mathematician’s design and construction of the bomba kryptologiczna — the cryptologic Bomb — which was the first electromechanical device used to support cryptanalysis.

The knowledge gained in Poland transformed GC&CS’s approach to Enigma cryptanalysis, and in January 1940, Alan Turing, who was by then working with Dilly Knox at Bletchley Park, travelled to Paris to meet the Polish cryptanalysts who had been evacuated to France after the fall of Poland.  Turing’s conversations with Marian Rejewski, the Polish mathematician and cryptanalyst were fundamental to developing the thinking which led to the design and installation of the first British "Bombe" which was working at Bletchley Park in time for the German Blitzkrieg in the West.


©GCHQ. The Bombe was used in Enigma cryptanalysis to recover message settings.