Thomas C. Sanger

America First Committee Rally, early 1940s Photo credit: American History USA

Why Don’t We Remember Athenia, Part 4

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When the British passenger ship Athenia was torpedoed and sunk on the first day of World War II, it took several days to assemble a comprehensive list of survivors, as well as the names of those who died. In the final counting, 30 Americans were among the 112 persons killed as a result of the attack. Despite the deaths of innocent U.S. civilians, America did not go to war with Germany following Athenia’s sinking.

Officially, the United States was a neutral country in the burgeoning war. Not long after the sinking, Americans who survived the attack began to ask the government to seek compensation from Germany for property they had lost on board Athenia. At the time, Germany was denying any responsibility for the attack (see blog post, Feb. 1, 2019), so the passengers’ requests put the U.S. government in a potentially awkward diplomatic position.

To preserve its neutrality, the U.S. State Department asked the American survivors to file affidavits detailing under oath what they saw and heard during the sinking. When all the accounts were gathered, respondents were notified that the State Department was “making a careful investigation with a view to determining the facts and responsibility for the sinking of the S.S. Athenia.” The department promised to give Athenia survivors details about preparing their claims if and when the investigation determined “a foreign government” was responsible for the damages suffered.

Based on information submitted by the survivors, the State Department could not conclusively establish that Germany was responsible for the sinking. Even though few people outside of Germany doubted that a U-boat had sunk Athenia, the recovery of damages would have to wait until after the war.

America’s neutrality was the result of strong isolationist sentiment in the halls of Congress and reflected the attitude held by many in the general public. Much of this sentiment carried over from World War I in the belief that the U.S. had been duped into helping England and France supposedly to make the world safe for democracy.

Entry into the war in 1917 eventually cost the lives of 53,000 American soldiers. Millions of dollars in loans made to allies during and after the war had not been repaid. These events had left a bitter taste in the mouths of many Americans. With Europeans once again going to war to settle their differences, isolationists contended this simply wasn’t America’s fight.

To be sure, many Americans, including President Franklin Roosevelt, felt strongly that the U.S. could not afford to ignore events in Europe and that the country should come to Britain’s aid. The president knew, however, that isolationist sentiment was too strong for him to expect Congress to support a declaration of war against Germany for the deaths of Americans aboard Athenia.

It wasn’t until two years later, when the Japanese attacked Pearl Harbor, that America was galvanized into action. By then, however, few Americans remembered that 30 of their fellow citizens had died Sept. 3, 1939, on the first day of the war.

Next month: The “rules of war” 

Karl Doenitz (top row, left, in sunglasses) listens to testimony at the Nuremberg trials following WWII. Photo credit: Newsmax.com

Why Don’t We Remember Athenia? Part 3

by Thomas Sanger • Thomas C. Sanger • Leave a Comment

Throughout World War II, Germany’s Nazi government denied responsibility for sinking the British passenger ship Athenia on the first day of the war. Their denial initially hinged on the fact that no U-boat had reported any action at the time and place where Athenia had been sunk (see blog, Jan. 1, 2019).

Even after the commander of the U-boat that torpedoed Athenia, Fritz-Julius Lemp, returned two weeks later to his base in Germany and admitted his mistake, the denials continued. German Chancellor Adolf Hitler is reported to have made the decision to continue the lie rather than reverse the denials of the previous two weeks.

While few outside of Germany believed the Nazi position, the continued denials raised vague concerns in some people’s minds that perhaps their might have been some other reason for the sinking.

In 1946, as prosecutors prepared for the war crimes trials at Nuremberg following World War II, they discovered discrepancies in the war diary (logbook) of U-30, the German submarine whose combat patrol zone included the location where Athenia was attacked. The first two pages were a different quality paper than the rest of the book. On these pages the months were recorded in Arabic numerals, while Roman numerals were used for the months in the rest of the book. Also, Lemp’s signature was an obvious forgery. The new pages showed U-30 nearly 100 miles from the spot where Athenia was torpedoed Sept. 3, 1939. The alteration was part of an elaborate, if clumsy, subterfuge started within 24 hours of Athenia’s sinking to convince the world that Germany wasn’t at fault.

The suspicious war diary wasn’t the only damning evidence to come to light. A German sailor who was aboard U-30 on that fateful evening and saw the sinking Athenia, had been taken prisoner during the war. With the war now over, the sailor no longer felt bound to maintain the defeated Nazi’s subterfuge, and he testified to what he had seen.

During a deposition prior to trial proceedings, Karl Dӧnitz, the former German submarine fleet commander and later Grand Admiral of the Navy, was confronted with the evidence. He readily confirmed that U-30 had sunk Athenia on the first day of the war.

His admission was only a stepping stone for the prosecutors, who wanted to show Dӧnitz was an unrepentant Nazi, guilty of far worse crimes than covering up the sinking of a passenger ship. By then, the world was learning of the horrors of Nazi death camps and the cold-blooded execution of millions of Jews and others deemed undesirable by the self-proclaimed master race.

Against this ghastly backdrop, the Athenia dead became little more than a footnote to the Nazi’s unspeakable crimes.

In next month’s blog: Why American deaths did not bring the U.S. into the war.

Fritz-Julius Lemp, U-30 commander, confers with Karl Doenitz, chief of U-boat operations. Photo credit: Galway Advertiser

Why Don’t We Remember Athenia? Part 2

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When Oberleutnant Fritz-Julius Lemp torpedoed and sank the British passenger ship Athenia at the beginning of World War II, he did not break radio silence to report his attack to his superiors. His decision led Germany’s Nazi government to deny responsibility for the sinking, a position they maintained for the duration of the war. That denial is undoubtedly a factor contributing to Athenia’s relative obscurity in historical accounts of the war (see blog, Nov. 30, 2018). 

The war was not quite nine hours old on Sept. 3, 1939, when Lemp, in command of U-30, torpedoed what he believed was a legitimate wartime target – an armed merchant cruiser. When he came to the surface after nightfall to assess how fast the ship was sinking, he discovered he had attacked an unarmed passenger ship, exactly the type of target his operational orders told him to avoid.

Lemp left the scene without breaking radio silence because, he later said, he did not want to betray his position to the British. Whatever Lemp’s reason for not reporting his action, it caught the German government flat-footed the next morning when news of a U-boat attack on an unarmed passenger ship began to circulate. Nazi officials immediately checked with naval authorities and received assurances that no U-boats had reported any action in the vicinity of the incident, which was correct but misleading.  Some U-boats had not reported at all, including U-30.  

The Nazis were eager to deny responsibility for the sinking because it gave England a major propaganda tool to use against Germany. Far worse, however, was the possibility that the attack on Athenia had killed Americans, which might bring the United States into the war. Germany’s Secretary of State for Foreign Affairs wasted no time the morning of Sept. 4, 1939, in offering Americans an official German denial of any responsibility for sinking Athenia. To assure world opinion that Germany was abiding by international treaties, Chancellor Adolf Hitler issued an order to all naval units that same day, warning that no passenger ships were to be attacked under any circumstances.

When Athenia survivors began disembarking in Galway and Glasgow a day later, they made it clear they thought their ship had been torpedoed and several said they had seen the submarine. In response the German press speculated Athenia may have been mistakenly attacked by a British submarine or had struck a floating mine. Within days, however, the Nazi’s chief propagandist, Joseph Goebbels, published an account that Britain’s new First Lord of the Admiralty, Winston Churchill, had planted a bomb on board Athenia in order to sink the ship, kill American passengers, and bring the United States into the war against Germany. 

Britain vehemently denied the allegations and few outside of Germany believed the Nazi assertions. Even so, the United States, which announced it would be a neutral party in newly declared war, refrained from blaming Germany in the absence of irrefutable proof, a sign of the isolationists’ political strength in the U.S.

The Churchill story had been circulating for two weeks when Lemp returned to his base in Wilhelmshaven and reported to Karl Dӧnitz, Germany’s submarine fleet commander, that he sank Athenia. At Hitler’s direction, German officials continued to deny responsibility for Athenia’s sinking through the remainder of the war.

In next month’s blog: The truth is finally revealed.

Young Athenia survivor arrives in Glaway, Ireland. Photo credit: The Telegraph

Why Don’t We Remember Athenia? Part 1

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The Second World War was a little less than nine hours old on Sept. 3, 1939, when a German submarine torpedoed and sank the unarmed British passenger ship Athenia. The incident not only was the opening shot of World War II’s longest continuous conflict – the Battle of the Atlantic – but also made Athenia the first British ship sunk by Germany in the war.

Seventy-nine years later very few people on either side of the Atlantic have ever heard of Athenia or know of the ship’s place in history. How such a singular moment could have faded from our collective memory is a question we will explore in my next four monthly blogs, beginning today.

The first of several factors helping to eclipse Athenia’s memory is the death toll: 112 men, women, and children died as a result of the U-boat attack. In 1915, during World War I, nearly 1,200 passengers and crew members died when the British liner Lusitania was torpedoed by a German U-boat. With a death toll more than ten times greater than that of Athenia’s, the Lusitania sinking is seared into the history books of World War I.

Like the peacetime tragedy of the Titanic, who’s sinking had claimed more than 1,500 lives in 1912, human beings seem prone to remember these greater catastrophes. Fortunately for most of the people aboard Athenia, the death toll from her sinking failed to reach such a threshold.

While U-30 fired at least three torpedoes at Athenia that fateful Sunday evening, only one struck home. It proved to be a mortal blow, but the ship remained afloat for nearly fifteen hours, more than enough time for her crew to launch all twenty-six lifeboats.

The launching process was complicated by the fact that the ship began listing to her port side, making it more difficult to lower the boats on her starboard side where they scraped down the hull on the way to the water. During the hour and twenty minutes it took to launch the boats, Athenia’s portside tilt held at a manageable five to six degrees.

Also assisting in the launching conditions was the fact that the Atlantic Ocean was relatively calm for early September. The wind would rise steadily through the night and into the following day, but it was not a factor for the first several hours after Athenia was torpedoed. The ship’s lifeboats were launched by hand, a process that would have been complicated had the seas been higher, particularly as Athenia’s engines had been knocked out and the ship would have been at the mercy of the ocean’s swells.

In the end, all but two of the ship’s twenty-six lifeboats made it through the night without mishap. Rescue ships responded quickly to Athenia’s S-O-S, the first appearing on the scene about six hours after the torpedo strike.

All of these conditions, plus the crew’s training and flawless execution of their duties, meant that the sinking of Athenia was not nearly the tragedy it might have been, one important reason why the ship’s loss has faded into history’s shadows.

In our next blog: Germany denies responsibility for the sinking.

Could you understand this Middle English conversation? Photo credit: NPR

Challenges of Historical Fiction Dialogue

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When an author tackles a subject of historical fiction, a number of considerations come into play. What are the living conditions the characters will experience for the given time period? What key details will make the period come alive for the reader: food, clothing, transportation, political/historical conditions, religious beliefs, medical or scientific knowledge?

Depending on the time period, most of these details are available in resources found in libraries, museums, and archives. But what does an author do about dialogue? In a novel, characters are going to speak to each other, and in some cases may even narrate the story. Making that language sound authentic is a critical element for bringing the reader into a historical novel’s timeframe.

To manage this feat, many historical novelists immerse themselves in the language of the period they are writing about. They absorb speech patterns, syntax, and any distinctive words that call to mind a particular time or place. For most of the 20th century there are multiple dialogue examples: radio and television transcripts and recordings, movies, books (including other novels), newspapers, speeches, letters, and diaries. These sources begin to drop away as the centuries recede, so the further back in time the story is set, the greater the challenge.

And yet, authors like Ken Follett, Bernard Cornwell, and Philippa Gregory manage to write hugely successful novels set in ancient times. How do they do it?

Fortunately, the historical novelist doesn’t need—and shouldn’t try—to exactly replicate the speech of a bygone era. Anyone who has struggled to read the Middle English of Geoffrey Chaucer understands that a novel set in the 14th century would bog down under the pretense of “authentic” dialogue. Regardless of a story’s historical setting, its characters’ dialogue must communicate with today’s readers.

Once an author becomes familiar with the language of a particular era, the task is to write dialogue that sounds authentic to the period, even though it primarily makes use of language familiar to current readers. The most obvious concern is to keep current slang or figures of speech out of the mouths of characters living decades or centuries before present day. Altering the syntax just enough to emulate the novel’s period gives it a feeling of authenticity. Likewise, having characters use a few unfamiliar words or idioms from the period can help dialogue ring true, but only if the meanings can be readily inferred by the reader.

As with any novel, the dialogue should never call attention to itself or cause the reader to step back from the narrative to wonder if a character would actually say what the author has written. The best dialogue is short and to the point. It uses common, everyday words to communicate information, ideas and emotions. To meet these guidelines and make the dialogue sound as if it is spoken by 12 century serfs or 18th century nobility, is a remarkable feat.

So the next time you read a historical novel whose characters convey powerful ideas and emotions in a vernacular that sounds authentic to the period, you can appreciate even more the artistry that goes into the work.

Sub-Lieutenant David E. Balme, R.N. Photo credit: The Telegraph

Enigma’s Mysteries Revealed

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Nearly two years after the start of World War II, the British Royal Navy for the first time put a boarding party onto a crippled German submarine. On May 9, 1942, 20-year-old sub-lieutenant David Balme led a party of nine sailors onto U-110, not knowing if the boat had been booby-trapped and half expecting scuttling charges to detonate at any moment.

Balme and his men had been sent across from H.M.S. Bulldog by her captain, Commander Joe Baker-Cresswell, with orders to gather up signal books and any other useful materials they might find (see blog post “Lemp’s Fatal Mistake, Aug. 30, 2018). Balme was the first man into the submarine, and when he was certain the boat had been abandoned, he called for the rest of the men to join him in the U-boat’s control room.

“The lights were still on and everything was lying about just as if one had arrived at someone’s house after breakfast, before they had had time to make beds, etc., coats were thrown around, bunks half made,” he later remembered. “There was complete silence in the U-boat except for the continual thud of our own depth charges [in pursuit of a second U-boat]…a most unpleasant and frightening noise.”

He told the men to ignore anything that was obviously casual reading material and to take whatever else appeared to be of interest. Speed was of the essence because U-110 was sinking and Balme was still concerned about explosive charges. Complicating matters was the fact that none of the men read German.

At one point, a sailor came out of the U-boat’s radio room and told Balme, “There’s something rather interesting I want to show you.” In the cramped radio room, Balme was shown a typewriter-like device screwed to the table. He could see that pressing one key on the machine caused a different letter to light up on a display. Balme told the sailor to unscrew it and send it up with the rest of the material being gathered. The young sub-lieutenant had no way of knowing that his party had just recovered the first working model of the German naval Enigma machine, a top-secret prize British Intelligence had coveted since the start of the war.

As the day wore on and the submarine remained afloat, Balme became less concerned about scuttling charges or the boat’s quick demise. At one point, Bulldog sent over sandwiches and a small boat to replace the one that had smashed itself on the U-110’s deck. He did worry, however, when Bulldog was called away on a U-boat sighting and a dense fog settled on the ocean.

“There was I, with my boarding party aboard U-110 in the middle of the Atlantic, alone with no ships in sight and with the wind and sea gradually increasing,” Balme recalled. Fortunately, Baker-Cresswell’s dead-reckoning navigation skills brought Bulldog back to the crippled submarine before nightfall, and the treasure trove of materials, including the Enigma machine and its codebooks, were transferred to the British destroyer.

By day’s end, Bulldog took U-110 under tow in hopes of delivering her to Iceland for careful inspection by British submarine experts. The next day, however, the U-boat sank en route. By then, the submarine’s capture and its trove of materials had been given a top-secret designation with the code name “Primrose.” Great effort went into limiting the number of people made aware of Primrose, and the capture was kept secret for several decades after the war.

U-110’s sinking may have been a blessing in disguise. Had the boat been towed to Iceland, it is entirely possible that local German spies would have relayed its capture to German authorities. German naval commanders would have assumed their encrypted communications could be compromised and they would have made changes to the Enigma machine and its codes much sooner than was actually the case. Even after the Germans made modifications in an effort to restore the naval Enigma’s integrity, insights gained by British intelligence from the materials taken from U-110 helped reduce code-breaking to a matter of hours or days instead or weeks.

At least one naval historian went so far as to characterize Operation Primrose on a scale commensurate with the outcomes of the Battle of Midway in the Pacific and the Battle of Stalingrad in Europe – not a bad day’s work for a Royal Navy convoy escort group and a junior naval officer barely out of his teens.

Crew from H.M.S. Bulldog prepares to board U-110 Photo credit: Wikipedia

Lemp’s Fatal Mistake

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The man who sank the unarmed British passenger ship Athenia on the first day of World War II, Kapitanleutnant Fritz-Julius Lemp, had managed to become a “U-boat Ace” in the 20 months of the war since his tragic mistake. Lemp had been credited with 22 ships sunk or damaged and awarded the Knights Cross, Germany’s highest award for valor. But in May of 1941 the brash, young U-boat commander’s luck was about to run out.

Two days after the Enigma code books for June were taken off the German trawler München (see blog post for Aug. 6. 2018), Lemp, now in command of U-110, attacked a westbound convoy off Greenland in the middle of the day. He fired a fan of four torpedoes at a horizon filled with Allied ships. Two shots struck home, adding two ships to Lemp’s tally. His third torpedo missed, and the fourth failed to launch from its tube. As Lemp waited at periscope depth to reset his forth torpedo for another shot, he was discovered by a British corvette that crippled U-110 with a depth charge attack.

Commander Joe Baker-Cresswell, the man in charge of the convoy escorts, was surprised to see U-110 pop to the surface in front of his flagship, H.M.S. Bulldog. He ordered his destroyer ahead at full speed, intent on ramming the U-boat, but thought better of it when he realized the Germans were abandoning ship. At almost that same instant, Kapitanleutnant Lemp was telling his radio operator not to worry about destroying the boat’s Enigma machine and code books, and to get off the ship immediately because it was sinking.

But U-110 did not sink, at least not immediately. Sensing a unique opportunity, Baker-Cresswell brought Bulldog to a stop just near U-boat He put David Balme, a 20-year-old sub-lieutenant, in charge of a boarding party and sent them off in small boat with instructions to gather up any signal books he could find on the submarine.

When they were nearly alongside the U-boat, their small boat was swept up by a large swell and smashed onto U-110’s deck. The men scrambled out onto the U-boat and climbed to the top of the conning tower, where Balme was surprised to find the entry hatch closed tight. Why close a hatch if the boat was intended to sink, he wondered? He opened the hatch and had to holster his revolver to climb down the ladder, feeling totally exposed if any Germans were still aboard.

“This was a nasty moment,” Balme later wrote, “one looked down below and wondered how many Germans were there. I went down the ladder to the lower conning tower where there was a similar closed hatch. On opening this hatch I found the control room deserted! Hatches leading forward and aft were open and all lighting on.”

He could hear air escaping somewhere in the U-boat, but there was no hint of chlorine, a deadly gas that could be produced by the boat’s batteries being submerged in seawater. For young Balme, the discoveries were just beginning, as we will see in our next blog.

German trawler Munchen is captured by a British destroyer. Photo credit: Warcovers website

Sea Battles Turn Tide of Events for Enigma Codebreakers

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After a brief lull in the Battle of the Atlantic during January, 1941, German U-boats began to sink increasing numbers of Allied ships: 47 ships in February and 50 ships in March. But in March, a naval engagement off the coast of Norway was about to produce a valuable prize for Britain’s Bletchley Park code breakers. (See my blog, “Decoding Enigma: Success and Setback,” June 18, 2018.)

During a March 4th British commando raid, a Royal Navy destroyer engaged in a brief gun battle that left a German trawler disabled and burning. While the Germans abandoned their crippled ship, a three-man boarding party went across to the trawler. The leader of the party, Lt. Sir Marshall Warmington, broke into a locked desk in the captain’s quarters and found a wooden box containing two small, ratcheted wheels. Although he hadn’t been briefed on the German Navy’s Enigma coding device, Warmington thought the box looked intriguing. He retrieved it and some unimportant looking papers.

The papers turned out to be a bonanza for the Bletchley cryptanalysts. They contained Enigma settings for February, helping the analysts read several encoded German Navy messages from the previous month. With the help of these “cribs,” the analysts were able to construct the German bi-gram (two-letter) table used in transmitting the Enigma settings for individual messages. Even with this advantage, however, the decoding process still took weeks to complete.

To speed up the process, the Royal Navy quietly began putting together plans to capture a U-boat or other German naval vessel in hopes of obtaining more current Enigma codebooks. Thus far in the war, however, the Royal Navy had realized only limited success in sinking U-boats, let alone capturing one.

At this point, a radio traffic analyst at Bletchley Park proposed an inspired solution. In looking through the decrypted messages, Harry Hinsley saw that the Germans were sending trawlers to the seas north of Iceland to observe and report the weather conditions back to naval headquarters. Hinsley believed these lonely ships were equipped with Enigma machines and codebooks in order to send and receive certain secret messages. If such a ship suddenly came under attack, he reasoned, the crew might think to throw overboard their Enigma device and current codebooks, but likely would be too panicked to take the time to retrieve and destroy the next month’s codes, locked away for safekeeping.

The plan worked exactly as envisioned. On the afternoon of May 7, 1941, a Royal Navy destroyer opened fire as it raced toward the German trawler München. Moments after the trawler’s crew were picked up by the British, a boarding party from the destroyer climbed aboard the München, and this time they were joined by a London-based Intelligence officer who had been told what to look for and where he was likely to find it.

As expected, München’s crew had disposed of the Enigma machine and current codebooks, but not the codebooks for June. Three days later, the June codes were delivered to cryptanalysts at Bletchley, a gift that would allow them to read the German Navy’s June radio traffic within hours of it being sent.

Yet even as this operation was being hailed, another trove of information was falling into Royal Navy hands, courtesy of the same U-boat commander whose attack on the passenger ship Athenia had begun the Battle of the Atlantic 20 months earlier. More about that dramatic action in our next blog.

Alan Turing, one of the leading British cryptanalysts at Bletchley Park. Photo credit: A & E Biography

Decoding Enigma: Success and Setback

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By the spring of 1940, British cryptographers had a general idea of how the German Naval Enigma cypher device worked, but could not break its code without “cribs” ( see my blog, “British Codebreaking and the Bletchley Park Connection,” May 31, 2018).

To read the Naval Enigma messages, Bletchley Park analysts needed to know identity and order of the three wheels used to send messages, plus the settings on the wheels, and the plugboard setup for the day the message was sent. All this information had to be transmitted to the Enigma operators in the field before they could decode messages. The question was, how did the operators obtain the information?

A significant breakthrough happened in late April when a Royal Navy destroyer captured a German trawler off the Norwegian coast. The Germans had managed to throw two bags overboard filled with codebooks and the ship’s Enigma device. The bag with the Enigma sank, but the second bag did not and was recovered.

That second bag contained coded messages along with their related plain text translations (valuable cribs needed to help break the Naval code). This information, along with the Enigma wheel and plugboard settings for two of the days, allowed Alan Turing and his associates to read the first German Naval messages since the start of the war, albeit nearly two weeks after they were sent. However, access to these messages helped Turing work out how the Naval Enigma indicators were sent (see my May 31, 2018, blog).

To read the messages in real time, the codebreakers would need a copy of the bigram (a two-letter configuration) table used to send the messages, and no bigram tables were recovered from the trawler. Undaunted, British cryptanalysts were able to use the cribs to work backwards and begin to fill in the bigram pairings. With enough cribs, they were able to reconstruct most of the bigram table in use at that time.

Turing devised a system to help eliminate most of the wheel positions not used to encrypt a message. The smaller number of remaining possibilities could then be tested using his “bombe,” a pioneering computer that worked out the eventual correct wheel positions. Through this sped-up trial-and-error methodology, cryptanalysts were able to break a few months-old Naval Enigma messages without first having the wheel or plugboard settings.

But in decoding one of the messages, Turing discovered that a new bigram table would be introduced July 1, 1940. The change sent Bletchley Park’s Naval Enigma deciphering efforts nearly back to square one. Despite this setback, the British had developed more effective tools and methods for breaking the German Naval codes.

Now, however, the question was whether they would be able to read the German messages in real time before the rising U-boat toll could starve Britain into submission.

Photo caption: Dr. Arthur Scherbius, German electrical engineer who developed the Enigma machine. Photo credit: Alchetron

The Evolution of Enigma

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In my last blog (“The Mystery of Enigma,” May 1, 2018), we explored the ingenious design of the German Enigma machine. The encryption device provided so many possible permutations for each letter in a message that it seemed impossible for Enigma’s code to be broken.

Despite Enigma’s close association with World War II, the device actually was developed at the end of World War I. Arthur Scherbius, the German engineer who created the Enigma, sought to interest the German navy and the Foreign Office in his newly patented design in 1919, but both turned him down.

Scherbius formed a company and exhibited his first machine in 1924 at an international gathering of postal officials. That first model, marketed under the brand name “Enigma,” incorporated an actual typewriter, weighed just over 100 lbs., and lacked many of the refinements of later models.
By 1927 Scherbius designed a machine that was lighter and more portable. The new model proved popular, and the company sold Enigmas to commercial markets in Europe, Scandinavia, the United States, and Japan. At about the same time, the German navy and army acquired upgraded Enigmas that included the plugboard design, a feature not available on commercial models.
Over the next decade, the German military models underwent further tweaks and upgrades to become even more inscrutable than their commercial cousins. For example, the army’s Enigma version incorporated a fourth wheel, while the navy continued to use the three-wheel design but introduced two additional wheels that could be interchanged with any of the three original wheels.

Beginning in the late 1920’s military intelligence operations in Britain, France and Poland set about trying to break the German military Enigma code. They had no success until late 1931 when an executive in the German Defense Ministry began spying for the French and provided a copy of the Enigma instruction manual as well as three-letter codes used to set up the machines.

This material was passed by the French to the Poles, who were further along with their decryption efforts owing to the Poles’ greater affinity with German engineering and their proximity to a re-arming German state. Using the spy’s information, Polish mathematicians succeeded in working out the internal wiring of each of the Enigma wheels, and in 1933 Polish intelligence built several prototype Enigmas and began to read German military communications. The Poles, however, did not inform the French or British of their success.

Every day each branch of the German military set their Enigma machines to a pre-arranged master setting which included the order of the wheels, the setting of the initial letter on each wheel, and the plugboard connections. From this arrangement, the sender transmitted a new random three-letter code for the initial wheel settings then adjusted the machine’s wheels to the new settings and typed the message. The receiver decoded the initial three letters, re-set the receiving machine’s wheels accordingly and decoded the message that followed.

The Poles used an arrangement of six prototype Enigmas to determine the wheel positions of the German machines each day. To read individual messages, they relied on the German practice of repeating the random three-letter setting at the beginning of each transmission.
The Polish cryptographers were able to keep up with most German modifications, reading military communications for nearly five years. On the eve of World War II the Germans made physical changes to their Enigma machines and changed code-sending practices, leaving Polish intelligence unable to “eavesdrop” on the German military. The battle to solve Enigma shifted to a new front, as we’ll see in our next blog.