The Black Code Theft[1]
The “Black Code” was a secret code used by the US Army to transmit sensitive information during World War II. The Italian Intelligence service, also known as the Servizio Informazioni Militare (SIM), intercepted and decoded messages sent using this code in September 1941, some three months before Pearl Harbor and the US declaring war on the Axis. This gave the SIM valuable information about the military plans and operations of the US and its allies.
However, CommandoSupremo says that the theft of the code book happened on 8th December 1941 (which, interestingly, allowing for time zone differences, might have been 7th December in Pearl Harbor – when the Japanese attacked the US fleet):
‘A group of the Sezione Prelevamento (Withdrawal Section) of Italian Army intelligence (SIM Servizio Informazioni Militari) led by Maj. (Carabinieri) Talamo break into the US embassy in Rome and steal a codebook known as the “Black Code”. They photographed the codes and put it back in the safe. These photos were used to decipher top-secret messages sent from Cairo to Washington D.C. about British strengths and weaknesses in Africa. This discovery was what gave Rommel the early successes in the desert war.’
Image Citation: “The Business of Spying: a Tiny Camera and a Big Mama Camera” by Can Pac Swire is licensed under CC BY-NC 2.0.
The compromise of the Black Code was a significant intelligence victory for the Italian government and likely had a negative impact on the Allies’ war effort. It is not absolutely certain how SIM intercepted and decoded the messages sent. Some historians believe that the SIM obtained a copy of the code itself, while others suggest that it was broken through advanced cryptanalysis techniques. It’s also possible that the Italian Intelligence Service benefited from its close relationship with the German intelligence service, the Abwehr, which had access to the most advanced cryptanalysis tools and techniques of the time and had a history of breaking the codes of their enemies. The Italian Navy’s cryptologists also achieved some success with Royal Navy codes and cyphers[2].
The US government were unaware that details of the Black code had been stolen from its Embassy in Rome by Italian spies in September 1941. Embassy worker Loris Gherardi took copies of the embassy keys. These were passed on to SIM, who were able to break in, copy, and replace the documents. The Italians did not pass the full code to the Chiffrierabteilung, their German counterparts, only providing limited information, such as decoded American messages, but the limited information still assisted the Germans in their own independent efforts, and they were also able to crack the Black Code.[3] According to HistoryNet[4], General Cesare Amè, head of SIM, approved a break-in of the (then neutral) US embassy in Rome in September 1941:
‘Since Amè had keys to all the embassies in Rome, except for the Russian, it was a simple matter to gain entry at night. The burglary team consisted of two Carabinieri (national paramilitary police) specialists and two Italians employed by the Embassy. One of the latter, messenger Loris Gherardi, opened the safe in the military attaché’s office.’
The Black Code (more formally, Military Intelligence Code No. 11) was used by US military attachés in the early period of World War II. The nickname comes from the colour of the superencipherment tables/codebook binding.[5] The code was compromised by Axis intelligence, the information leak costing a great many Allied lives. From mid-December 1941, Germany could read the reports of Bonner Frank Fellers[6], US military attaché in Cairo. Fellers’ radiograms provided detailed, extensive and timely information about the Alies’ troop movements and equipment.:
- The messages alerted the Axis to the British convoy operations in the Mediterranean Sea, including efforts to resupply the garrison of Malta.
- Beginning in January 1942, information about the numbers and condition of British forces was provided to General Erwin Rommel, the German commander in Africa. He could thus plan his operations with reliable knowledge about the opposing forces.
- The Germans referred to Fellers as “die gute Quelle” (“the good source”). Rommel referred to him as “the little fellow”.[7]
Fellers was appointed Brigadier General in 1942, during World War II. He was best known for his role in investigating the Italian dictator Benito Mussolini and his involvement in the decision not to capture or kill him after his fall from power. One reliable source of information about Bonner Frank Fellers is the book The Most Unsordid Act: Lend-Lease, 1939-1941 by Warren Kimball. This book provides a detailed account of the role of the United States in providing military aid to the United Kingdom and other allies before and during World War II and includes information about the activities of American officials, including military attachés like Fellers. Written by a historian who is a specialist in the field of diplomacy and international relations, it’s a well-documented and well-researched book. The Johns Hopkins University Press published it in 1969.
In June 1942, the British informed Washington that the “Cairo Code” was compromised, and the US Army Signals Intelligence Service promptly sent a SIGABA machine to Cairo. The leak ended on 29th June, when Fellers switched to the new US code system. However, some, like Colonel Alfred McCormack, were unconvinced and suspected that the British were reading the dispatches in the American “Black” code, not the Germans. McCormack finally concluded that was not the case, but not before considerable ill feeling had been aroused (Churchill had told Roosevelt in February 1942 that he had stopped British work on American diplomatic codes, a warning to tighten them up). Meanwhile, the Allies benefited from reports by Japanese attachés in Germany[8] and Ambassador Hiroshi Ōshima.
September 1941
The code was compromised by Italian intelligence in September 1941. It is believed that embassy worker Loris Gherardi took copies of the embassy keys, which were then passed on to the Italian Military Intelligence Service (SIM). They broke into the US embassy, copied the documents, and replaced them without detection. SIM did not pass on the full code to the German Chiffrierabteilung, only providing limited information, such as decoded American messages. However, the limited information still assisted the Germans in their own independent efforts, and they were also able to crack the Black Code.
As for Loris Gherardi, there is limited information available on his fate. It is unknown whether he was caught or punished for his actions in providing the keys and copies of the code to the Italian Military Intelligence Service (SIM). Some records indicate that Gherardi was arrested by the Americans after the war and was tried and convicted of espionage. Others suggest that he had been able to escape prosecution and live a normal life in Italy.
A paper at the Public Broadcasting Service (PBS) notes[9]:
Although the British worried about the possibility of American security leaks, they began sharing decoded Enigma messages and diplomatic reports about the war. British security fears were justified, for these exchanges soon gave Rommel his own intelligence breakthrough. Reports on the British campaign in North Africa were sent regularly to Washington by the US military attaché in Cairo. The Germans intercepted the messages but couldn’t break the diplomatic code.
‘Then, in September 1941, the Italian secret service broke into the US embassy in Rome and stole the code book used to encipher all U.S. diplomatic messages. The thieves copied the codebook and returned it to the safe without anyone knowing. Now Rommel could read all embassy transmissions about the British campaign. Armed with information about British troops and tanks, Rommel launched a bold assault through Libya, pushing the British back 300 miles in 17 days.
‘The news that reached Churchill painted a grim picture of defeat. Now the British needed their own intelligence coup to reverse the disaster. At Bletchley Park, the codebreakers raced to crack the daily rotor settings. Some breaks came in only six to 12 hours. Still, lives might be saved if the operation could be speeded up. The gifted codebreaker Alan Turing had long been intrigued by the idea of building machines to automate the codebreaking process. The Poles had built such a device before the war, but Turing set out to improve on their ideas. Turing’s goal was to build a machine that could figure out how the German operators had set up their Enigmas for that day’s messages. Using stock phrases, or cribs, to deduce the rotor settings was the most time-consuming part of the whole codebreaking process.’
Before modern computer methods, special machines were used to encrypt and decrypt text messages. Close-up of the rotors in a cypher machine. Citation at End Note[10]
Who were the Axis?
During World War II, the Axis powers, which included Germany, Italy, and Japan, were constantly trying to gain access to codes used by the Allies. For example:
- The Germans broke the British naval code, allowing them to track and attack Allied ships more efficiently.
- The Japanese broke the American code used by the military, which led to the surprise attack on Pearl Harbor in 1941.
- Abwehr, the German intelligence service, attempted to infiltrate the British intelligence service and gain access to secret codes and information.
Image Credit: Germany’s Führer Adolf Hitler (right) beside Italy’s Duce Benito Mussolini (left).
Attribution: Bundesarchiv, Bild 146-1969-065-24 / CC-BY-SA 3.0, CC BY-SA 3.0 DE <https://creativecommons.org/licenses/by-sa/3.0/de/deed.en>, via Wikimedia Commons.
Page URL: https://commons.wikimedia.org/wiki/File:Bundesarchiv_Bild_146-1969-065-24,_M%C3%BCnchener_Abkommen,_Ankunft_Mussolini.jpg
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The Axis powers (originally called the Rome–Berlin Axis)[11] was a military coalition that initiated World War II and fought against the Allies. Its principal members were Nazi Germany, the Kingdom of Italy, and the Empire of Japan. Although the Axis were united in their opposition to the Allies, they lacked close coordination and ideological cohesion.
The Axis grew out of successive diplomatic efforts by Germany, Italy, and Japan to secure their own specific expansionist interests in the mid-1930s. The first step was the protocol signed by Germany and Italy in October 1936, after which Italian leader Benito Mussolini declared that all other European countries would thereafter rotate on the Rome–Berlin axis, thus creating the term “Axis”.[12] The following November saw the ratification of the Anti-Comintern Pact, an anti-communist treaty between Germany and Japan; Italy joined the Pact in 1937, followed by Hungary and Spain in 1939. The “Rome–Berlin Axis” became a military alliance in 1939 under the so-called “Pact of Steel“, with the Tripartite Pact of 1940 formally integrating the military aims of Germany, Italy and Japan and later followed by other nations. The three pacts formed the foundation of the Axis alliance.[13]
At its zenith in 1942, the Axis presided over large parts of Europe, North Africa, and East Asia through occupation, annexation, or puppet states.
Code-Breaking and Deception Tactics
Both sides used a variety of methods, including codebreaking, infiltration and sabotage, to gain access to the enemy’s secrets, codes and other classified information from the enemy. It wasn’t only codebreaking that ultimately gave the Allies the upper hand. They also employed deception tactics to mislead the Axis powers.
The Enigma machine was a device used by the Germans to encrypt their communications during World War II. The Allies were able to break the code used by it, allowing them to read German communications and gain valuable military intelligence. Alan Turing and his team at Bletchley Park, Milton Keynes, Buckinghamshire, were instrumental in breaking the Enigma code, and their efforts are credited with significantly shortening the war. Valuable work was also carried out at “Broadway” (54 Broadway, near Westminster, London), the location of MI6’s London office during WWII, and before that, it was the location of GC&CS (Government Code and Cypher School) from 1926 to 1939.
Another example is the breaking of the Japanese “Purple” code by American cryptanalysts, which allowed the US to read diplomatic messages sent by Japan and provided valuable intelligence that helped to prepare for the Battle of Midway in 1942, which was a major turning point in the Pacific War. The breaking of the Italian naval code by the British was another success. The British cryptanalysts were able to read the Italian naval communications and track the movements of Italian ships, which helped the Allies to gain an advantage in the Mediterranean.
The following are further examples of the many codebreaking and intelligence operations that took place during World War II. The efforts of codebreakers and intelligence agencies on both sides played a significant role in the war’s outcome.
- Operation Mincemeat was a British plan to mislead the Germans about the Allies’ plans to invade Sicily in 1943. The operation involved planting false documents on a dead body, which was then washed ashore in Spain and discovered by the Germans, who believed the documents were genuine.
- The breaking of the German “Fish” code by Polish and French cryptanalysts before the war and later by British and American cryptanalysts during the war. The “Fish” code was used by the German navy and airforce, and the intelligence gained from breaking the code provided valuable information about German naval and airforce movements.
- The breaking of the Japanese “JN-25” code by American cryptanalysts at the US Navy’s cryptographic centre in Hawaii, Station HYPO. The intelligence gained from breaking the code provided valuable information about Japanese naval movements, including the movement of the Japanese fleet before the attack on Pearl Harbor.
- The American’s “Magic” broke the Japanese diplomatic code, which provided valuable information about Japanese diplomatic negotiations and plans. This intelligence was used to anticipate and prepare for Japanese military actions.
- Operation Ultra was a British intelligence operation during World War II, enabling the decryption of high-level German military communications encrypted by the Enigma machine. It was one of the most important intelligence sources for the Allies during the war, providing valuable information about German military plans and movements.
- The British Government Code and Cypher School at Bletchley Park broke the German “Railway” code, which provided valuable information about German military movements and logistics.
- The American’s “Black Chamber” broke the Japanese “Red” code, which provided valuable information about Japanese diplomatic communications.
- NKVD, the Soviet Union’s intelligence agency, broke the German “Geheimschreiber” code, which provided valuable information about German military plans and movements on the Eastern Front.
- The British Special Operations Executive (SOE) employed the use of secret ink and microdots to send encrypted messages to resistance groups in occupied Europe.
- Operation Bodyguard was a deception operation carried out by the Allies before the Normandy invasion. The operation was intended to mislead the Germans about the location and timing of the invasion, and it was successful in keeping the Germans guessing about the true location of the landing.
- The British Government Code and Cypher School at Bletchley Park broke the German “Lorenz” code, which provided valuable information about high-level German military communications and strategic plans.
- The American “SIS” (Signals Intelligence Service) broke the Japanese “JN-25b” code, which provided valuable information about Japanese naval movements and plans.
- The British Special Operations Executive (SOE) used radio direction finding (RDF) to locate and track German radio transmissions.
- The American “OSS” (Office of Strategic Services) was able to infiltrate German intelligence and sabotage German military operations in Europe.
- Operation Fortitude (1944): This was a deception operation conducted by the Allies before the D-Day invasion of Normandy. It involved creating a fake army and convincing the Germans that the Allied invasion would occur in Calais instead of Normandy.
- Operation Overlord (1944): This was the code name for the D-Day invasion of Normandy on June 6, 1944. The operation was a massive undertaking that required careful planning and coordination between various intelligence agencies.
- Operation Garbo (1942-1945): This was a British double agent operation in which a Spanish businessman named Juan Pujol García passed himself off as a Nazi spy. He provided the Germans with false information, leading them to believe that the D-Day invasion would take place, not in Normandy but elsewhere.
- Operation Bodyguard (1944): This Allied deception operation was conducted before the Normandy invasion. It aimed to mislead the Germans about the invasion’s timing and location and divert German attention and resources away from Normandy. The operation successfully misled the German military about the timing and location of the Normandy landings, allowing the Allies to gain a foothold in occupied Europe.
- Operation Canaris (1939-1945): This German intelligence operation aimed to gather information on the Soviet Union. The outcome is unclear, and details are not well-documented, but it is believed that it had limited success in translating and analysing British naval signals.
- Operation Monastery (winter 1941) was a Soviet intelligence operation during World War II in which a Soviet agent, Aleksandr Demyanov, posed as a member of an anti-Bolshevik and monarchy-sympathising group called “Prestol” to gain the trust of German forces and gather intelligence on their plans and movements. It was conducted using a false identity and was one of the most successful intelligence operations in the history of the USSR. The operation’s name was ‘Монастырь’ (“Monastyr”; English, “monastery”).
The examples I have listed above show that codebreaking and intelligence operations played a major role in WWII. It was a constant battle between both sides to gain an advantage over the enemy. Some examples include:
- In 1941, German spies stole plans for the British naval code, which allowed the Germans to track and attack Allied ships with greater efficiency.
- In 1942, German intelligence stole plans for the American M-209 cypher machine, used by the American military to encrypt messages.
- In 1942, Japanese intelligence was able to steal plans for the American “Purple” code, which was used by the American State Department to encrypt diplomatic messages.
- In 1944, German intelligence was able to steal plans for the American “SIGABA” cypher machine, used by the American military to encrypt messages.
- In 1944, Soviet intelligence was able to steal plans for the German “Tunny” cypher machine, which was used by the German military to encrypt messages.
The examples show that both the Axis and Allies’ powers were actively trying to steal each other’s codes and other classified information to gain an advantage in the war. Spies and agents working behind enemy lines often carried out these thefts, providing valuable intelligence that helped shape the war’s course.
Many of the intelligence operations, thefts, and spying activities during World War II were highly secretive, and the identities of those involved were often not revealed. Some of the information about these activities may have been classified and not been made public.
During World War II, many individuals and groups were involved in intelligence operations and espionage activities on behalf of both the Axis and Allied powers. Some notable examples include:
- The Cambridge Five was a group of British spies who passed information to the Soviet Union.
- The Red Orchestra was a Soviet spy network active in Germany and occupied Europe.
- The Double Cross System was a British counterintelligence operation that successfully turned German spies into double agents.
- The Manhattan Project was a top-secret research project that developed the first atomic bombs.
- The Nuremberg trials, where many high-ranking Nazi officials were tried and convicted for war crimes, some of whom were involved in espionage.
Spies and Agents in World War II
Several spies from World War II and agents are well known for their actions and contributions to the war effort. Here are a few examples:
-
- Alan Turing: A British mathematician and computer scientist who played a crucial role in breaking German codes, including the Enigma machine. He was also one of the pioneers of theoretical computer science and artificial intelligence. See Image Credit in End Note[14].
- Virginia Hall: An American spy who worked for the British Special Operations Executive (SOE) in occupied France. Despite having a prosthetic leg, she played a key role in organizing resistance groups and helping Allied soldiers evade capture.
- Julia Child: Before becoming a famous chef and television personality, Julia Child worked as a research assistant for the Office of Strategic Services (OSS), the precursor to the CIA. She served in Ceylon and China, where she was responsible for decoding and transmitting classified messages.
- Rudolf Abel: A Soviet spy who operated in the United States under the alias “Emil R. Goldfus.” He was eventually arrested, tried, and convicted of espionage in 1957.
- Richard Sorge: A German spy working for the Soviet Union who operated in Japan. He provided crucial information to the Soviet Union about Japan’s intentions to remain neutral during the war and its plan to invade the Soviet Union. See Image Credit in End Note[15].
- Oleg Penkovsky: A Soviet military intelligence officer who provided the West with crucial information during the Cold War, particularly about Soviet missile capabilities.
- Lorenz Schmidt: A German spy who operated in the United Kingdom under the alias “Walter Dicketts.” He was arrested by the British and later executed.
- Harold Cole: An Englishman who worked as a spy for the German Abwehr during the war. He was later hunted down and killed by the French Resistance.
- Duško Kondor: A Yugoslavian spy who worked for the Abwehr in the United Kingdom and North Africa. He was captured by the Allies and later executed.
- Edward Arnold Chapman: known as Eddie Chapman, he was a British criminal the Germans recruited as a spy. During World War II, he offered his services to Nazi Germany as a spy and later became a British double agent, providing false information to the Germans while also helping the British with counterintelligence. In acknowledgement of his erratic personal history, his British Secret Service handlers codenamed him Agent Zigzag. He was awarded the Nazis’ Iron Cross for bravery while serving as a double agent for Britain. See Image Credit in End Note[16].
- Odette Sansom: A British spy who worked for the SOE in occupied France. She was captured and sent to a concentration camp but survived the war.
- Fritz Kolbe: A German diplomat who passed information to the British during the war and is considered one of the war’s most important spies.
- Andrée Borrel: A Frenchwoman who worked as a spy for the British SOE in occupied France. She was captured and executed by the Nazis.
The above is not a complete list. Some individuals were caught, but many others were not, and their identities and contributions may have remained classified and unknown. The nature of espionage means that it is often difficult to determine the true extent of an individual or group’s involvement, as they were never publicly identified or acknowledged, and many details may remain classified or unknown even today.
All these examples show that codebreaking and intelligence operations played a major role in WWII, a constant battle between the different sides to gain an advantage over the enemy. Both sides used various methods to gain access to the enemy’s secrets, including codebreaking, deception, infiltration, and sabotage.
Image Credit: Hitler declaring war on the United States on 11 December 1941
Attribution: Bundesarchiv, Bild 183-1987-0703-507 / unbekannt / CC-BY-SA 3.0, CC BY-SA 3.0 DE <https://creativecommons.org/licenses/by-sa/3.0/de/deed.en>, via Wikimedia Commons
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Sources and Further Reading
- https://annaabi.ee/e1hkr-o.html
- https://comandosupremo.com/1941/
- https://en.wikipedia.org/wiki/Black_(code)
- https://en.wikipedia.org/wiki/Bonner_Fellers
- https://en.wikipedia.org/wiki/German_code_breaking_in_World_War_II
- https://everything.explained.today/Black_(code)/
- https://forum.axishistory.com/viewtopic.php?t=51589
- https://friendsintelligencemuseum.org/2015/08/18/fellers-in-cairo-die-gute-quelle/
- https://histclo.com/essay/war/ww2/code/ncb/w2ncb-ita.html
- https://www.dni.gov/files/NCSC/documents/ci/CI_Reader_Vol2.pdf
- https://www.historynet.com/intercepted-communications-a-secret-ear-for-the-desert-fox-september-96-world-war-ii-feature/
- https://www.nsa.gov/portals/75/documents/about/cryptologic-heritage/historical-figures-publications/publications/wwii/pearl_harbor_revisited.pdf
- https://www.nsa.gov/portals/75/documents/about/cryptologic-heritage/historical-figures-publications/publications/wwii/west_wind_clear.pdf
- https://www.wikiwand.com/en/Black_(code)
- https://2009-2017.state.gov/documents/organization/176704.pdf
- https://www.archives.gov/iwg/declassified-records/rg-226-oss/entry-211.html
Books and PDFs:
- European Axis Signal Intelligence in World War II, Volume I, Synopsis. DOC ID 3560861, (PDF). Army Security Agency.
- The Codebreakers – The Story of Secret Writing, by David Kahn (ISBN 0-684-83130-9)
- Intercepted Communications for Field Marshal Erwin Rommel, by Wilfred P Deac, at The History Net.
- Battle of Wits: The complete story of Codebreaking in World War II, by Stephen Budiansky (2000). New York: Free Press (pp. 260, 267, 268) ISBN 0-684-85932-7.
- The Most Unsordid Act: Lend-Lease, 1939-1941 (Paperback), by Warren F. F. Kimball (Author), published by Johns Hopkins University Press (1 December 2019), available at: https://www.amazon.co.uk/Most-Unsordid-Act-Lend-Lease-1939-1941/dp/142143072X/
- The Secret War: Spies, Codes and Guerrillas 1939–1945 (Paperback), by Max Hastings, published by William Collins (5 May 2016), available at: https://www.amazon.co.uk/Secret-War-Max-Hastings/dp/0007503903/
- Code Name: Lise: The True Story of Odette Sansom, WWII’s Most Highly Decorated Spy (Official UK Edition) (Paperback), by Larry Loftis, published by Mirror Books (20 February 2020), available at: https://www.amazon.co.uk/Code-Name-Odette-Decorated-Official/dp/1912624710/
- The Last Cambridge Spy: John Cairncross, Bletchley Park Mole and Soviet Agent (Paperback), by Chris Smith (Author), published by The History Press (27 January 2022), available at: https://www.amazon.co.uk/Last-Cambridge-Spy-Cairncross-Bletchley/dp/0750998601/
- ZigZag: The Incredible Wartime Exploits of Double Agent Eddie Chapman (Paperback), by Nicholas Booth (Author), published by Piatkus (29 May 2007), available at: https://www.amazon.co.uk/ZigZag-Incredible-Wartime-Exploits-Chapman/dp/0749951540/
- Nazi Spies and Collaborators in Britain, 1939-1945, by Neil R Storey, due to be published on 31 March 2023 by Pen and Sword Military, available at: https://www.amazon.co.uk/Nazi-Spies-Collaborators-Britain-1939-1945/dp/1399084321/
- Alastair Denniston: Code-Breaking from Room 40 to Berkeley Street and the Birth of GCHQ, by Joel Greenberg, published by Frontline Books (1 September 2017), available at: https://www.amazon.co.uk/Alastair-Denniston-Code-breaking-Berkeley-Street/dp/1526709120/
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End Notes and Explanations
- Source: The machine-generated answer given to the request– ‘What is it that was known as the Black Code’, and supplementary questions at: https://chat.openai.com/chat ↑
- Source: https://histclo.com/essay/war/ww2/code/ncb/w2ncb-ita.html ↑
- Source: Intercepted Communications for Field Marshal Erwin Rommel, by Wilfred P Deac, at The History Net. ↑
- Source: https://www.historynet.com/intercepted-communications-a-secret-ear-for-the-desert-fox-september-96-world-war-ii-feature/ ↑
- Source: David Kahn, The Codebreakers – The Story of Secret Writing (ISBN 0-684-83130-9) ↑
- Explanation: In October 1946, Bonner Frank Fellers reverted to the rank of Colonel as part of a reduction in the rank of 212 generals. He retired from the US army on 30 November 1946. In 1948, his retirement rank was reinstated as Brigadier General. ↑
- Source: Intercepted Communications for Field Marshal Erwin Rommel, by Wilfred P Deac, at The History Net. ↑
- Source: Battle of Wits: The complete story of Codebreaking in World War II, by Stephen Budiansky (2000). New York: Free Press (pp. 260, 267, 268) ISBN 0-684-85932-7. ↑
- Source: https://www.pbs.org/wgbh/nova/transcripts/2615decoding.html ↑
- Image Attribution: The original uploader was Matt Crypto at English Wikipedia., CC BY-SA 3.0 <http://creativecommons.org/licenses/by-sa/3.0/>, via Wikimedia Commons. Page URL: https://commons.wikimedia.org/wiki/File:FIALKA-rotors-in-machine.jpg This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. Subject to Wikipedia General Disclaimers. ↑
- Source: Goldberg, Maren; Lotha, Gloria; Sinha, Surabhi (24 March 2009). “Rome-Berlin Axis”. Britannica.Com. Britannica Group, inc. Cited at: https://en.wikipedia.org/wiki/Axis_powers ↑
- Sources: (1) Cornelia Schmitz-Berning (2007). Vokabular des Nationalsozialismus. Berlin: De Gruyter. p. 745. ISBN 978-3-11-019549-1, and (2) “Axis”. GlobalSecurity.org. Cited at: https://en.wikipedia.org/wiki/Axis_powers ↑
- Source: Cooke, Tim (2005). History of World War II: Volume 1 – Origins and Outbreak. Marshall Cavendish. p. 154. ISBN 0761474838. Cited at: https://en.wikipedia.org/wiki/Axis_powers ↑
- Image Credit: “Alan Turing” by Christopher_Hawkins is licensed under CC BY-NC-ND 2.0. ↑
- Image Credit: “RICHARD SORGE–NOT MY PHOTO” by roberthuffstutter is licensed under CC BY 2.0. ↑
- Image Credit: Eddie Chapman (1914-1997) aka Agent ZigZag – double agent. Attribution: Unknown British photographer., Public domain, via Wikimedia Commons. Page URL: https://commons.wikimedia.org/wiki/File:Eddie_Chapman_(Agent_ZigZag).jpg ↑