Tag Archives: Enigma

Bill Tutte-Worthy of Remembrance


“In all our long history we have never seen a greater day than this. Everyone, man or woman, has done their best.”

Winston Churchill, 8th May 1945

As I sat watching all the pomp and circumstance in Whitehall this morning, I considered all those whose contributions are not so recognised on Remembrance Day.  It would be an impossible task (and indeed a very long blog) to list all those who contributed to the war effort; so today I chose to think of those who through intellect and determination used their brilliant minds to break codes that were believed unbreakable.  Naturally, my mind turns to Bill Tutte and his fellow code breakers at Bletchley Park

(c) BBC

Professor Brian Cox and Captain Jerry Roberts
(c) BBC

Captain Jerry Roberts frequently recounts his experience of being in the same office as Tutte:

“I saw him staring into the middle distance, twiddling his pencil, and making counts on reams of paper; and I used to wonder whether he was getting anything done.  My goodness he was.  It was an extraordinary feat of the mind”. 

Captain Jerry Roberts

Tutte applied the Scientific Method to deduce the logical structure of Lorenz:

 “…by using logic, careful observation and by producing testable hypotheses, he managed to determine exactly how it worked.”

Professor Brian Cox


Simulation of Tutte’s Periodicity Examination
(c) BBC

Bill Tutte has been described as a shy and unassuming man.  It’s amazing to think of Tutte sat quietly with paper and pencil performing one of the greatest intellectual feats of World War Two. Tutte worked away on the problem for months.  He never gave in.  So today on Remembrance Sunday, let us remember those who fought with intellect and determination; Those who used their brilliant minds to achieve the seemingly unachievable; Those whose efforts contributed to shortening the war and saved countless lives.

For too long these great minds have gone without recognition, with your support we can give Tutte recognition he deserves.



Author: Claire Butterfield


The Turning of the Tide

Almost all the literature about the achievements of Bill Tutte, the Bletchley Park code breaker who cracked the German Lorenz code in 1941, a code vastly more complex and strategically more significant than the well known Enigma that the Polish and then Alan Turing cracked, says that he was credited with contributing to shortening the Second World War in Europe by up to two years, saving countless lives.  Some attribute this saying to General (later President) Eisenhower, the Supreme Allied Commander, and some even to Churchill himself. No matter, but how could such an incredible achievement be made by just one man, or even a small team?

After the entry of the USA into the war in December 1941, many believed that eventual victory was inevitable.  What was far from certain is when that would be.  Churchill even feared that it could take until 1950.  He knew it would take years for the formidable American economy and industrial capability to transform onto a war footing, and he was fearful of a premature engagement in Europe that could result in defeat by the battle-hardened German armies.  The Battle of Kasserine Pass in February 1943 when Rommel’s Afrika Korps routed poorly led and untested American troops in Tunisia proved his point.  Similarly, the disastrous Dieppe landings in August 1942 had shown how inadequate forces could not hope to land on strongly defended coastal positions.

Bill Tutte’s achievement enabled the Allies to read the signals traffic between Hitler and his prime operational headquarters, giving invaluable information about German strategic intentions and capabilities.  Churchill and Roosevelt had realised at an early stage that Russia held the key to defeating Hitler and, as well as providing the Russians with prodigious amounts of war equipment, the supply of strategic information to them was critical.  The surrender of German forces at Stalingrad in the winter of 1942/3 allowed the Russians to move onto the offensive.  Hitler was determined to crush them and to avenge the defeat at Stalingrad.  In July 1943, 3000 German tanks faced almost twice that number of Soviet heavy armour at Kursk, 280 miles South West of Moscow, in the largest engagement of armour ever to have taken place.

Although heavily outnumbered, the German tanks were far superior in armour and fire power.  However, delays in German arrivals allowed the Russians to prepare formidable defences and to concentrate their forces.  Moreover, German misgivings about the forthcoming battle led to much signals traffic using the supposedly invincible Lorenz code machines.  Thanks to Bill Tutte, the British were able to read this traffic.  (British radio technology was far ahead of that of both the Germans and Russians, neither of whom could believe signals traffic in Russia could be intercepted in Britain.)  The British were able to give their Russian allies almost the complete German order of battle, leading to a stunning Russian victory which they rightly called the Turning of the Tide.  General Zhukov, the Russian commander, was so impressed with the information he had been given that he thought the British must have had a mole in the German Headquarters, which in effect we did.

Afterwards, the Russian advance into Germany and eventually to Berlin was unstoppable, but it did ensure the engagement of up to 100 Divisions of crack German troops with countless tanks and aircraft on the Eastern front for the rest of the war.  This massive diversion of German resources allowed the successful Allied invasion of Normandy on 6 June 1944, but only after intercepted Lorenz traffic had satisfied Eisenhower that Hitler was convinced that the invasion would come at the Pas de Calais.    The final defeat of Nazi Germany in May 1945 can be linked directly to the work of Bill Tutte.

Ironically, it was mistrust of the Russians that led to Bill Tutte receiving no recognition or award for his war winning achievement.  We never admitted to the Russians that we had cracked the Lorenz code.  After the defeat of Germany, the Russians used captured Lorenz machines for their own coded messages throughout the early days of the Cold War, without realising that British security services could read the traffic.  To have recognised Bill Tutte’s achievement would have given the game away.  It was not until nearly 50 years later, after the collapse of the Soviet Union, that his story came out.  Even now, much remains secret.

You can donate via https://mydonate.bt.com/charities/billtuttememorialfund

Author: Richard Fletcher

Bill Who? The Lesser Known Codebreaker of Bletchley Park

The work of Bletchley Park during the Second World War is inspirational-numerous codes were broken and incalculable lives were saved. It is important to remember that code breaking at Bletchley Park was a team effort and not something that one person could have achieved alone. However, some people are prominent due to their unique contribution; Bill Tutte was one of those people.
W. T. (Bill) Tutte

W. T. (Bill) Tutte

“Bill who?” Is the standard response I receive whenever I mention his name. If I’m lucky, then the person to whom I am speaking has heard of Bletchley Park and Enigma, and if it is a really good day then they have heard of Alan Turing; but it is rarely the case that they have heard of Lorenz, Colossus, Bill Tutte or Tommy Flowers.
A Naval Enigma Machine

A Naval Enigma Machine

So let me clarify. Alan Turing cracked the Enigma code as used by the German Army, Navy and Air Force. It was a cipher transmitted via Morse code and was an important tactical code to break. The breaking of Enigma is widely remembered for its significance when tackling U-boat threat during the Battle of the Atlantic. When we talk about Tutte, Flowers and Colossus, this is in reference to the Lorenz cipher-an enciphering attachment to a teleprinter machine. Lorenz was used by the German High Command, so a break into Lorenz revealed the strategy of Hitler and his generals-highly significant communications during World War Two.
Lorenz SZ42

Lorenz SZ42

So what was Bill Tutte’s contribution to the breaking of Lorenz?
Very simply, Tutte deduced the structure of the Lorenz cipher through analysis of two pieces of cipher text where the original messages had been enciphered using the same settings, but with slight differences between the texts (e.g abbreviations and misspellings). This meant the encipherment could be removed and then Tutte could look for recurring patterns within the text, eventually deducing the entire structure of the machine. This enabled Tommy Flowers to design and build Colossus, the world’s first digital computer, which was used to break the Lorenz cipher. Tutte’s achievement has been described as the greatest intellectual feat of the Second World War, because unlike Enigma, Tutte deduced the structure of Lorenz with no information about the machine or what it looked like.
Surely that deserves a memorial?
Author: Claire Butterfield