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Gustave Bertrand – Research Notes

Basic Facts

Full name: Gustave Bertrand Born: 1896 Died: 1976 Nationality: French Service: French Army / Deuxième Bureau / French Secret Service Final rank: General (retired) Codename given by Poles: Bolek

Career Overview

Bertrand joined the French military as a private in 1914 and was wounded in 1915 at the Dardanelles. He returned to service and from 1926 worked in radio intelligence. By the end of 1930, French military intelligence reorganised its decryption work and created Section D (Decryptement) within the Deuxième Bureau; Bertrand became its chief. He later took over all of French radio intelligence.

His role made him the key broker between intelligence collectors (agents and subagents) and cryptanalytic consumers (France’s allies).

Role in the Enigma Break

Recruiting Schmidt’s Material

Through his network, Bertrand came into contact with Rodolphe Lemoine (born Stallmann, codename “Rex”), a German-born French agent who in turn cultivated Hans-Thilo Schmidt – a German civil servant at the Chiffrierabteilung with access to Enigma operating documents and key tables.

Schmidt’s first delivery of Enigma materials at Verviers, Belgium occurred on 8 November 1931. Bertrand received the documents via Lemoine and recognised their potential immediately.

Approach to the British

Bertrand first offered Schmidt’s materials to the British Government Code and Cypher School, specifically to Dilly Knox and GC&CS. The British were unable to make use of them – a fact that would later prove deeply embarrassing.

Delivery to Poland

In approximately December 1932, then-Captain Bertrand personally carried Schmidt’s documents – including the September and October 1932 Enigma key tables – to Polish Cipher Bureau chief Major Gwido Langer in Warsaw. He made the approach without knowing what the Poles had already achieved.

What he did not know: Marian Rejewski had already formulated the mathematical apparatus to crack Enigma and was waiting precisely for this type of material to close the equations. The documents, arriving around 9–10 December 1932, reduced Rejewski’s unknowns enough for the rotor and reflector wirings to be recovered. The Enigma was broken within weeks.

The Poles gave Bertrand the codename “Bolek.”

Rejewski later acknowledged: “the intelligence material furnished to us should be regarded as having been decisive to solution of the machine.”

The Pyry Meeting (July 1939)

Bertrand learned the full extent of what the Poles had achieved only at the tripartite Polish-French-British conference at Pyry, south of Warsaw, on 25–26 July 1939 – five weeks before Germany invaded Poland.

He had been delivering materials to Poland for seven years. He now discovered that those materials had enabled the complete reconstruction of the Enigma machine and the reading of German military traffic since 1933. The revelation was staggering.

The French delegation at Pyry: Bertrand and Captain Henri Braquenie (Air Force staff).

The Poles revealed everything: methods, wiring, cyclometer, bomba kryptologiczna, Zygalski sheets. They promised each delegation a Polish-reconstructed replica Enigma machine.

Bertrand’s reaction was not recorded with the same dramatic detail as Knox’s, but his account of the meeting in his 1973 book confirms the delegations’ astonishment and describes the atmosphere as electric.

Wartime Activities: PC Bruno and Cadix

After Poland fell, Bertrand organised a continuation of the Franco-Polish cryptological work in France.

PC Bruno (Poste de Commandement Bruno): established October 1939 at the Chateau de Vignolles near Gretz-Armainvilliers, some 40 km south-east of Paris. Polish Cipher Bureau cryptologists including Rejewski, Rozycki, and Zygalski worked there under cover identities alongside French and Spanish Republican codebreakers. Rejewski worked under the cover name “Pierre Ranaud.”

Cadix (Chateau des Fouzes, near Uzes, southern France): established October 1940 after the fall of France, operating in the Unoccupied Zone under the Vichy regime. The centre continued reading German and Italian dispatches about Axis troop movements in North Africa and elsewhere until the German occupation of Vichy France in November 1942.

Rozycki had been sent from Cadix to the branch office in Algiers; he drowned on his return voyage when the SS Lamoriciere sank on 9 January 1942.

When the Germans occupied Vichy France in November 1942, Cadix was evacuated. Rejewski and Zygalski ultimately escaped via the Pyrenees, Spain, and Gibraltar to reach London in August 1943.

Capture and Escape

On 5 January 1944, the Germans captured Bertrand at Sacre-Coeur basilica in Paris. In a high-stakes deception, Bertrand pretended to cooperate, was allowed to return to the Unoccupied Zone, and immediately went into hiding with the French Resistance.

On 2 June 1944 – four days before the D-Day Normandy landings – at an improvised airstrip in France’s Massif Central, Bertrand, his wife, and a courier of the Polish Resistance boarded a small, unarmed Lysander III aircraft that flew them to southern England.

(Note: some sources describe the courier as a Jesuit priest; the Wikipedia article on Bertrand identifies the passenger as “a Jesuit priest who served as a courier of the Polish Resistance.”)

Later Life

Bertrand retired from the French Secret Service in 1950.

He became mayor of Theoule-sur-Mer, a commune on the Cote d’Azur.

In 1973, he published Enigma, ou la plus grande enigme de la guerre 1939–1945 (Paris: Plon), providing the first detailed French-language account of the eleven years of Franco-Polish collaboration. The book gave Bertrand’s personal view of events and remained an important primary source, though its accuracy has been disputed in some details by later scholarship.

He died in 1976 – three years after his book appeared, and three years before the story reached an English-language audience through Garlinski’s Intercept (1979) and Kozaczuk’s Polish W kregu Enigmy (1979).

Historical Significance

Bertrand occupies a unique position in the Enigma story: he was the essential middleman who connected Schmidt’s treason to Rejewski’s mathematics. Without him the French documents would never have reached Poland – the British certainly couldn’t use them. Without those documents, Rejewski’s break would have been slower, more speculative, and possibly incomplete.

The chain runs: Schmidt sells to Lemoine – Lemoine delivers to Bertrand – Bertrand carries to Langer – Langer passes to Rejewski – Rejewski cracks Enigma. Remove any link, and the chain fails.

Bertrand also deserves credit for organising PC Bruno and Cadix, which kept the Franco-Polish cryptological effort alive for three years after Poland’s fall, allowing the Poles to continue contributing to Allied intelligence until November 1942.

Sources