Deceit on D-Day Outtakes from Victory and Deceit
compiled by Albert A. Nofi
The Traffic Desert
As a portent of things to come, the Allies established the tactic of creating "traffic deserts" up to a hundred miles behind the German front line during the Battle for France in 1944. Hundreds of fighters and two engine bombers were assigned to these areas throughout the daylight hours. Any vehicles seen moving were attacked (included any railroad traffic that had survived the bombing attacks even deeper into the enemy rear). The Germans soon learned that to move a vehicle in daylight was to loose it. As a result, mechanized units had to move at night, meaning that they moved at less than half their normal speed. Vehicles attempting to move in daylight were invariably attacked. The targets found in daylight were often senior officers taking a chance making a high speed dash in their staff cars. Erwin Rommel was one such victim, nearly being killed when his car was strafed by an Allied fighter.
Deceiving the Germans: Overlord's Bodyguard
"Operation Overlord", the amphibious landings in Normandy that would be forever known as "D?Day," was the most complex and risky undertaking in the history of warfare. To insure that the invasion had every chance of success, the Allies developed an elaborate series of deceptions, all, in the words of Winston Churchill, designed to provide the truth with "a bodyguard of lies." While several of these often elaborate deceptions will be treated separately elsewhere in this book it seems convenient to summarize them here.
- Ferdinand: a plan designed to convince the Germans that the Allies intended to make their principal thrust in the Mediterranean in Italy, to the exclusion of a "secondary" invasion in southern France or the Balkans.
- Fortitude North: an amphibious invasion of central Norway. Since Hitler was particularly sensitive about the security of Norway, which was an important source of iron ore and a valuable base in the war against the Russian convoys, this was a fairly elaborate deception, and was quite successful.
- Fortitude South: an amphibious invasion across the Straits of Dover against the Pas de Calais, the most direct and logistically easy invasion route, albeit the riskiest, since the Germans could read maps as well. As a result, this was the most elaborate of all the cover plans, and the most successful. The deception was maintained for nearly two months after D?Day as a way of convincing the Germans that the Normandy landings were actually a diversion. In effect, the Allies managed to convince the Germans that the enormous Normandy operation was one huge feint.
- Glimmer: a simulated assault landing against Boulogne, near the Pas de Calais, on D?Day itself, to pin down German troops during the initial hours of the invasion.
- Ironside: a threatened landing against Bordeaux and southwestern France, intended to keep German troops away from Normandy for as long as possible.
- Royal Flush: a series of diplomatic deceptions designed to suggest that various neutrals (Sweden, Spain, and Turkey) might be contemplating joining the Allies, or at least allowing them air base rights or similar benefits.
- Taxable: a simulated assault landing against Fecamp, just north of Normandy on D?Day itself, to pin down German troops during the crucial first hours of the invasion.
- Vendetta: an invasion of southern France. Since the Allies actually intended to land in southern France (Operation Anvil/Dragoon), this was a truly tricky trick. First the Allies had to mount a convincing threat, and then, once the D?Day landings had actually taken place, that this threat was for a second landing, to occur within a week or so of the Normandy operation. But then the Germans had to be convinced that that it had all been a ruse after all, so that they would begin to strip away troops to support the fighting further north, in time for the real landings, which occurred with considerable success on August 15, 1944, about a month after the Vendetta cover plan was blown by the transfer of the troops involved from North Africa to Italy.
- Zeppelin: a series of deceptions designed to suggest that the principal Allied thrust would be in the Balkans, either against Pola, at the head of the Adriatic, of on the Dalmatian coast, or in Albania, Greece, Crete, or against Romania, or some combination of several of them simultaneously.
Note that these are not all of the cover plans which were designed to protect the secret of D?Day. There were others, not all of which were as elaborate, such as "Copperhead", in which an actor who greatly resembled British Field Marshal Bernard Law Montgomery was flown to Gibraltar and thence to Algiers, where he held staff conferences with various prominent officers from the Mediterranean Theater on the eve of D?Day, in the hope that the Germans would lower their guard. And then there was "Titanic," four airborne landings simulated by thousands of half?sized dummies which were scattered over a wide area of northwestern France, designed to confuse the Germans in the opening hours of the actual invasion.
The Balkans Deception: "Operation Zeppelin"
The object of "Operation Zeppelin" was to pin German troops in the Balkans so that they would be weaker in France in anticipation of the Normandy landings. This was a very elaborate scheme, involving not merely the U.S. and Britain, but also Russia. The deception actually hinted at several Allied offensives, to be conducted either singly or in concert. In summary, the various operations involved an Allied offensive against:
- Peloponessus, the southernmost peninsula of mainland Greece.
- The Dalmatian Coast of Yugoslavia
- Mainland Greece
- The Coasts of Romania and Bulgaria (in cooperation with the Russians)
- Pola and the Istrian Peninsula at the head of the Adriatic, assuming the success of one or more of the earlier operations (items A through E).
The object of the plan was to keep major German formations in the Balkans for as long as possible. The idea was to convince the Germans that a major Allied move in the Balkans could be expected in mid?March of 1944, possibly in conjunction with the a new Soviet offensive. As the Normandy operation drew closer, the details of "Operation Zeppelin" were modified.
As developed in February of 1944, "Zeppelin" suggested an Allied offensive against Crete, the Peloponessus, Albania, and Dalmatia, or some combination of these, around March 23, 1944, around the new moon, to be supported by a Allied?Soviet assault on Romania and Bulgaria, plus an Allied landing on the Greek mainland in late April. As March 23rd neared, "technical difficulties" forced the postponement of the operations against Crete, the Peloponessus Dalmatia, and Albania until late April, with the assaults on mainland Greece and in the Black Sea therefore "necessarily" postponed until late May. But those pesky "technical difficulties," mostly as very real shortage of landing craft (the available landing craft being hoarded in Britain for the main event, D?Day), forced a further "postponement." As a result, going into late April, all assaults were rescheduled for late May. And yet again there were problems, so that finally the operations against Crete, the Peloponessus, and in the Black Sea were "canceled" so that those against mainland Greece, Albania, and Dalmatia were to take place in mid?June. By then, of course, the Normandy landings had taken place.
"Operation Zeppelin" seems to have been a success, keeping the Germans just sufficiently anxious about their situation in the Balkans to prevent the transfer of one or two mobile divisions to France. So the deception was helpful militarily. In fact, politically it was remarkably successful, in an unanticipated way.
One of the formations "committed" to "Zeppelin" was the Polish III Corps, consisting of two Polish divisions, the 2nd Armored and the 7th Infantry. Concentrated in southern Italy, this impressive force was supposed to conduct an amphibious landing against Durazzo, the principal port of Albania, with the intent of driving on the capital, Tirane, while other Allied forces (i.e., the U.S. Seventh Army, whose real objective was southern France as part of "Operation Anvil/Dragoon"), landed in Dalmatia and Istria. In reality, the Polish III Corps did not exist, save for one tank brigade, which was hardly capable of a major amphibious undertaking. The rest of the corps consisted of notional formations created by British specialists in deception. So successful was this bogus threat to Albania, that it had serious repercussions in high diplomatic circles. By early 1944 the Allies had committed themselves to supporting Marshal Tito's Partisans in Yugoslavia rather than the Royalist "Chetniks," who seemed as willing to fight Tito as the Germans. And Tito wanted nothing to do with Polish troops in the Balkans. A little elementary geography will explain why. Although not part of the Balkans, an independent Poland would be sufficiently strong to assert its will in that region assuming no interference from even stronger outside powers.
Tito's objections to Polish troops "intruding" into the Balkans created a major problem for "Zeppelin" planners. They could not inform Tito of the deception, since his headquarters was riddled with German sympathizers and spies. Nor could they "replace" the Polish troops in the operation with others, more politically acceptable to the Yugoslavs, since building up the existence of notional units was difficult and time consuming. In the end, the directors of "Zeppelin" decided to carefully continue to deceive the Germans as to the presence of the Polish III Corps, while deceiving Tito as to its absence. Fortunately for inter?Allied unity, they did not have to do so for long, as "Zeppelin" was abandoned after the landings in southern France.
The Phantom Army
Military deception attained unprecedented levels of sophistication during the war. The British and Americans created what amounted to an entire "phantom army" in order to fool the Germans. So successful were they in this effort that the Germans were convinced that the U.S. Army had some 20 percent more divisions than was actually the case, and the British Army nearly 70 percent!
The U.S., for example, created one army group (the "First United States Army Group," or "FUSAG", on which see below), one army (the "Fourteenth Army"), three corps, one armored division, five airborne divisions, and fourteen infantry divisions during the war for the specific purpose of deceiving the enemy. In addition, a further airborne division and nine infantry divisions which had been officially activated but not actually raised were more or less incorporated into this notional army, so that there were a total of 30 non?existent divisions officially part of the U.S. Army, a paper augmentation of about a third above actual divisional strength.
The creation of a "phantom" unit was surprisingly difficult. Initially it was almost impossible due to a peculiarity of U.S. Army regulations, which required the activation of new divisions on American soil. These restrictions had to be lifted before the creation of notional units for the purposes of deception could be undertaken. Things did not actually get going until 1943, by which time the British had been at it for years. Deception divisions were sometimes assigned numbers which fitted quite logically into the existing order of battle. For example, the Germans were aware of the existence of armies numbered from "First" through "Tenth," as well as a "Fifteenth," so that a "Fourteenth" sounded reasonable. And the notional "46th Infantry Division" followed neatly upon the existing 45th Infantry Division, while the "22nd Infantry Division" did appear to be logical, given that there were already a 23rd, 24th, and 25th Infantry Divisions. However, some ghost units were given designations similar to those of existing formations, so that there was a notional "6th Airborne Division" as well as a real 6th Infantry Division, and a "17th Infantry Division" as well as a 17th Airborne Division. The idea was to be as confusing as possible. And some of the notional units had impassively high numbers, such as the "157th Infantry Division," to suggest that there were a lot more U.S. divisions out there than was really the case (89, plus six of Marines).
Of course, in order to be confused, the Germans had to find out about these outfits. A variety of techniques were used to assist them in discovering the new formations. Double agents proved very useful for passing false order of battle information to the Germans, and even real enemy agents could be tricked into serving the Allied cause in this way. Other techniques included false radio traffic, "lost" documents, "accidental" slips of the lips in bars, and things like marriage notices in newspapers, wherein the groom's assignment was carefully noted.
One particularly clever trick involved National Geographic Magazine. The magazine was given official assistance in preparing a lavish full?color spread of U.S. military insignia, including army shoulder patches. The army cleverly arranged to have inserted among the legitimate insignia properly designed patches for most of the notional formations. Then, after only a few copies of the issue had been printed, the Army had the presses stopped. Within a few days a revised version of the insignia issue (June, 1943) was issued, with several interesting deletions. Some copies of the original version of the magazine were, of course, allowed to get into circulation. This was already a pretty clever ruse, but then a bit of luck occurred to reinforce it.
Since the Army's heraldic design people were themselves unaware that the formations for which they had been requested to design insignia were fraudulent, they not only designed quite attractive and symbolic patches, they also issued proper manufacturing specifications for them. Needless to say, an enterprising capitalist down on Seventh Avenue (New York City's "Fashion Avenue") quickly produced samples of these insignia in the hopes of securing the contract! And the Army promptly bought some thousands of them, which were actually issued to troops at times: Troops heading overseas were sometimes issued these false patches at their ports-of-embarkation. So one way or another the Germans soon got wind of the "existence" of the these formations. In passing, it might be added that copies of the magazine in question are worth a considerable sum today, as are the insignia, some of which were actually worn, when units bearing the appropriate designations were later raised in the postwar years.
Patches for Phantom Army
In their creation of notional units for the purpose of deceiving the Germans, the British used several techniques not employed by the Americans. They occasionally "created" a new division by the simple expedient of redesigning an existing one. Thus, their 77th Division became the 45th. While a small staff maintained the fiction that the original formation was still in existence, the new one began to appear in German intelligence reports. They also designated training and holding formations as divisions, which was in fact the case with both the 77th and its successor. In addition, they would sometimes designate a territorial command which had few or no combat troops as a division. For example, they created a "7th Infantry Division" on Cyprus with three notional brigades, two of which had the same numbers as outfits on distant colonial postings. Finally, they would sometimes shuffle units between the British and Indian Armies, so that the 36th Indian Division was transferred to the British Army as the 36th Infantry Division.
All this trickery turned out to be quite effective at fooling the Germans. The British were particularly successful. In fact, they were so successful that it can be difficult to trace formations even now, some fifty years later! On a world wide-basis the Germans overestimated Western military strength by some 60 divisions. They overestimated American strength by 20 percent and British strength by a remarkable 70 percent, representing something like a million additional combat troops. In terms of D?Day, this meant that the Germans believed there were over 40 percent more Allied divisions in Britain than was actually the case, some 85 to 90 infantry and armored divisions plus seven airborne divisions, when the actual figures were about 35 and three. It was an effort well worth the expense.
|Strength of the Allied Phantom Armies|
Arguably the total of notional Allied divisions could easily be increased. The U.S. 2nd Cavalry Division, a mostly black outfit which went to North Africa in early 1943, continued to be counted in German intelligence estimates until the end of the war, despite the fact that it had been disbanded some months after the end of the Tunisian Campaign. Likewise the Germans appear to have never caught on to the fact that the U.S. disbanded a number of National Guard cavalry divisions shortly after mobilization. And then there was the British 18th Infantry Division, which continued to turn up in Germans estimates of Allied strength, despite the fact that in early 1942 it had been captured by their Japanese Allies at Singapore.
The "First United States Army Group"
One of the most important deceptions of the "Bodyguard of Lies" with which the Allies protected the Normandy landings was "Operation Fortitude South." This involved a notional formation under the command of George S. Patton himself, the "First United States Army Group," known as "FUSAG" for short. FUSAG was supposedly concentrated in eastern Britain, perfectly located for an invasion of the Pas de Calais, that part of France lying closest to England.
Altogether about two dozen divisions were theoretically under Patton's command. Some of these were real outfits which just happened to be stationed in East Anglia. Most of his divisions, however, were fakes. On the eve of the Normandy landings virtually all of his divisions were notional ones, for as the real ones moved out, new false ones were created. As a result, on D-Day, June 6, 1944, FUSAG had under command 13.5 divisions, of which only 2.5 were real (including Britain's Guards Armored Division, retained on the theory that the Germans would expect so prestigious a unit to take part in the invasion), the balance consisting of three phantom airborne divisions (one British), two phantom armored divisions (one British), and six phantom infantry divisions (two British). These were organized into several notional corps, and FUSAG also had under command the headquarters of U.S. Ninth Army, a real formation awaiting transfer to the Continent.
Each of Patton's notional divisions had a few hundred men assigned. These included about two dozen signal corps personnel, assigned to simulate a division's worth of radio traffic. Aside from establishing the existence of the division, many of their messages were designed to suggest (sometimes blatantly) that the invasion was scheduled for the Pas de Calais ("Are we supposed to take all these VD cases to Calais with us!"). Most of the troops assigned to each notional division were engineers. They maintained and operated elaborate dummy installations (like dummy barracks and workshops), weapons, (like rubber tanks, guns, and trucks) and equipment (such as noise? and dust?making machinery) that helped strengthen the ruse. A lot of set designers and other folks in similar trades were recruited from the theatrical and motion picture industries to serve in these units.
FUSAG was an extremely successful ruse. Although a few senior German officers believed otherwise, virtually all of the senior officers, including Rommel and Rundstedt, overall commanders in the West, were convinced that the Pas de Calais was to be the principal Allied objective. The FUSAG ruse was maintained for weeks after the Normandy landings, in order keep the German Fifteenth Army pinned to the Pas de Calais. Since Patton was scheduled to command the Third Army as soon as sufficient maneuvering room had been secured in Normandy, an even more senior officer, Lieutenant General Lesley J. McNair, chief of the Army Ground Forces, was brought from Washington to "assume" command of FUSAG. As luck would have it, McNair was accidentally killed by "friendly fire" (actually "friendly bombs"; all that could be found of him was his West Point class ring), while observing the preliminary bombardment for "Operation Cobra," Patton's offensive designed to breakout of the beachhead to the south and spread out over France. Since by then the FUSAG ruse had pretty much run its course, it was quietly abandoned.
FUSAG was perhaps the most important single deception of the war. Although the Allies had deceptions hinting at a variety of alternative landing sites (see "Deceiving the Germans: Overlord's Bodyguard," above), there really were only two wholly practicable places, Normandy and the Pas de Calais. Had the attempt to deceive the Germans into believing the invasion was to come at the latter place failed, the Normandy landings would have been a much tougher proposition.
The XX (Double Cross) System
One of the more remarkable deceptions of World War II was the British ability to compromise the entire German spy system within Great Britain. Throughout the war, with very few exceptions, every spy the Germans had operating within Britain was caught by the British and, in most cases, turned into double agents working for the British. Naturally, this situation presented the Allies with numerous opportunities to deceive the Germans and this is exactly what happened.
Pulling off this feat was made possible by many factors. First of all, British counter-intelligence was good to begin with and throughout the 1930s the British knew who most of the German spies were. Rather than just arrest every German spy that was uncovered, the British allowed many to continue operating, but kept an eye on what they did and who they did it with. This enabled the British to stay on top of German espionage activities, as the Germans had no incentive to increase the security of their spy network. The Germans cooperated by not being as professional as they could have been. One benefit (to the Allies) of the Nazis taking over in Germany was the ascent of many Nazi politicians to prominent positions in the German security agencies. These Nazis generally had contempt for the professionals they now supervised, and that contempt was returned in kind. The strained relations between the Nazis and professionals in the German security apparatus lowered the efficiency of those organizations. This provided ample opportunities for the more professional British counter-intelligence to unravel German espionage activities in Britain. There was also the question of exactly who Wilhelm Canaris, the head of German Army intelligence (the "Abwehr") was working for. There is much evidence that Canaris was not totally on the side of his Nazi masters. In fact, M.I. 5 (British Intelligence) and the C.I.A. were quick to see the Canaris' widow was well taken care of after the war. To this day, no one in either intelligence establishment will say whether or not Canaris was working for the Allies.
After the war began, the British decided to attempt to "turn" the German spies rather than just arrest and execute them (the traditional way to deal with spies in wartime). But this did not happen all at once. When known German spies were rounded up in late 1939 (after war was declared), the British were content to simply have smashed any incipient German espionage activity in their country. Before hanging the spies, British intelligence attempted to extract as much useful information as possible from them. The British were in a strong bargaining position, as they could offer a prison term in lieu of the gallows to cooperative spies. During 1940, as the questioning of the spies continued, it occurred to some of the British interrogators, and their superiors, that it might be possible to "turn" many of the captured spies (have them pretend to remain German spies but actually work for the British). The British had not released a lot of information on the captured spies. At most, they announced that His Majesty's government had the German espionage problem under control. The Germans expected many of their pre-war spies to get caught when war broke out, and most of the others to lie low until things calmed down.
In late 1940 the British finally decided to attempt "turning" as many of the captured German spies as possible and to, in effect, control all German espionage operations in Britain. Many of the captured spies were given an offer they could hardly refuse; become a double agent or be executed for wartime espionage. Most German agents accepted this offer and spent the rest of the war feeding their controllers in Germany false or misleading information. This became known as the "XX (Double Cross) System."
What made XX remarkable was that the Germans never caught on. This feat was accomplished largely because the British were also reading German codes (the ULTRA system) and were thus able to feed the Germans real secrets that would not be damaging to the Allies cause. For example, the XX agents could radio true information to Germany on where Allied warships were. But this was only done when the ULTRA crew knew were all German submarines were and knew that none were in a position to take advantage of this. Other forms of harmless information passed on were things the Germans were going to soon find out anyway. Items like meetings of senior Allied leaders (which eventually hit the papers), the introduction of new weapons (which eventually hit German troops) and sundry (harmless) trivia that only someone inside Britain could find out (like what the Royal Family was up to). All of this was done to maintain the trust of the German spymasters for those situations when the Allies wanted to feed the Nazis false information in order to gain a military advantage. In other words, for when the Allies wanted to stage a deception.
It took several years to get the XX system working to everyone's satisfaction. This took a lot of effort on the part of the British. One mistake could have brought the entire system crashing down. The Germans didn't suspect something as outrageous as XX, so they proceeded on the assumption that they had a functioning spy system in Britain. This meant that new agents were sent in, and sometimes they tried to bring spies back to Germany. This last item gave the British fits, as they could not trust any of their XX spies to get back to Germany and not expose XX. Thus an elaborate deception had to be mounted to convince the Germans that new spies could get in, but old ones (that the Germans had hired in Britain or sent in) could rarely get out. Taking care of new German spies was much easier. They were made "the offer they couldn't refuse" and promptly became XX agents. Some did refuse, and were hung. These executions were made known to captured German agents who had not yet agreed to join the XX system, as well as those who already had. It encouraged all concerned.
The turned German agents were a mixed bag. Some were highly skilled Nazi true believers (the kind who tended to prefer death before dishonor), but most were a rather eclectic collection of adventurers, misfits, idealists (who were willing to compromise) and the like. The Germans knew they had a mixed bag of spies and were happy to get anything at all useful out of them.
There were never more than about 50 XX agents to be looked after, and most of these were low level operatives. That is, they were ordinary citizens, often working at menial jobs. They did not have access to the inner workings of the British government or the military and could, at best, simply report what they saw as they went about their daily routine. To make the XX system more believable, and the job of the British controllers easier, periodically one of these agents would "disappear." This was natural in the espionage business. Agents got caught, or lost their nerve and stopped spying. The Germans also had their problems in meeting their payroll. Agents had to be paid, and to take care of this chore couriers came in from Germany via the neutral nations of Portugal and Spain. The British did not make it easy for these couriers to make their rounds, and would arrest and jail them as it suited their purposes. For example, a courier coming through with the payroll could be nailed, thus causing one or more agents to go off line because they hadn't been paid. Sometimes, XX agents would send a last message saying, in effect "they are on to me" and then disappear.
The information concocted for the XX agents to radio back had to be plausible. Because of the mundane lifestyles of most agents, they could only report on those things a waiter or office worker could have access to. Travel was restricted in wartime Britain, so agents couldn't wander far afield looking for military information. Agents were expected to read the newspapers and listen carefully to pub talk and whatever rumors were floating around the civilian population. In large port cities, one could observe the ship traffic and report it. A bicycle ride near some military installations might yield some interesting insights.
The British did manage to insert some of their own agents into the German network. These were often "new" spies that the original XX agents "recruited" in England. There were also people who escaped Nazi occupied Europe or had language and other skills that made them suitable for espionage work. These people were "recruited" by the XX network of phony German agents and were allowed to travel back to Europe to meet with their German controllers. Naturally, few of these agents knew about the XX system. The details of XX were kept by a small circle of British intelligence operatives. But this was standard espionage practice. The less any individual knew, the less would be lost if that agent were caught and interrogated.
The Germans also turned British agents on the continent, but because of the XX system and ULTRA, the British minimized the damage these turncoats caused. Sometimes, the British were able to turn these agents once more, making them British agents turned by the Germans but actually working for the British. It was a murky business, as espionage always was. It was one area of human endeavor where paranoia was a positive trait.
From the beginning of the XX system in late 1940 through 1943, the British were grooming their XX agents for bigger things. Until 1944, there was little opportunity to use the XX system for any really big deceptions, mainly because most of the fighting was going on in Russia. Oh, XX was used to assist the war against German U-boats in the Atlantic, and to support the relatively minor operations in North Africa. But when 1944 came along, so did the preparations for the Allied invasion of France. This undertaking was to involve massive deceptions and XX played a major role.
Since the D-Day invasion was being launched from Britain, the Germans put their British spy network into high gear. The Germans also sent many more new agents to Britain, and this put a much heavier workload on the XX staff, as all these new spies had to be captured and "turned" into XX agents. All this had to be done carefully, lest that one fatal slip up compromise the XX system when it was needed most.
One of the risks the XX staff enchanted was the normal espionage procedure which allows for a captured spy, who is forced to turn, to send a signal in one of his coded messages to indicate that he was now a captive. Armed with such knowledge, the Germans could have played a little game on the British. This was a risk the British had to accept and it took time before they were sure the Germans were hooked. While the British were running the XX agents, they also had ample opportunity to uncover German operations on the continent. Although the Germans were careful to tell their agents in Britain no more than they needed to know, there were ways the British could use the XX agents to reveal information about German espionage operations elsewhere. This was often as simple as passing some information about a certain fake Allied espionage operation on the continent and then note who did what as a result. The Allies also had the assistance of their ULTRA intercepts. Thus, while getting ready to use XX for the big invasion in 1944, the British were able to run a lot of smaller, but still valuable, deceptions on the German spy system.
One of the more valuable items picked up was the cipher used by German spies when they radioed their messages. Since the XX spies had to use this, the Germans sent them the new ones every time the code was changed (periodically, to make it harder to crack). This saved the Allies a lot of effort in cracking this particular code and allowed the Allies to quickly read the messages of other spies (in neutral countries like Spain, Portugal, Switzerland, Turkey and Sweden) and act on what they read. By reading these messages, the Allies were able to glean massive amounts of information on what the Germans were up to and what the Nazis were thinking.
The information requests the Germans made of their agents were also quite revealing, as it indicated what they didn't know, and what they were interested in knowing more about. As these requests were in support of upcoming German operations, this gave the Allies a good idea of what was going on inside the minds of the German leaders.
Best of all, although some Germans grew suspicious at times, the Nazi high command was never convinced that their espionage network was compromised to the extent that it was. The Nazis were not simply being blind, for the Gestapo (German secret police) and Abwehr (German military intelligence) were having some success in the occupied countries. But this success would have been much greater had the Allies not possessed XX and ULTRA.
The capstone of the XX effort was the deceptions the Allies played on the Germans in support of the invasion of Normandy in June, 1944. This deception attempted to do nothing less than make the Germans believe that the Normandy operation was not THE main invasion, but rather a feint. Given the size of the Normandy operation, this deception would appear an impossible task. But the Allies managed to pull it off, in no small part because of the "trustworthy" network of agents the Germans had in Britain. For over a month after the Normandy invasion, the Germans held back many of their strongest armored divisions so that they could deal with the "second" invasion. The second invasion never came because it was a deception, one of the most successful in military history. Thousands of Allied lives were saved and the defeat of the German forces in France came sooner because of this deception.
The XX system also paid many other dividends. It assisted in the war against German submarines in the Atlantic and saved the lives of many Allied agents on the continent. But as valuable as the XX system was, it was kept secret for over twenty years after World War II. This was partially because of the Cold War, and the need to use some of the XX tricks against the Soviet Union. But the Communists were no slouches in the espionage department, and knew all about XX long before it was revealed to the public in the 1970s.
ULTRA, the Grand Deception
During World War II (1939-45), the Allies were able to read German secret codes, and thus set the Germans up for a monumental bit of deception. The code breaking project was called ULTRA.
For a quarter century after World War II, one of the grandest military deceptions ever undertaken went unknown except to the small group of people who pulled it off. The secret was ULTRA, which was the code word for the successful British effort to break the secret codes the Germans used for the messages they transmitted. Such secret codes had become big business in the 20th century as the volume of daily messages needed to keep modern armed forces going increased dramatically. Every major nation took care to make sure their codes were difficult to decipher, and that the codes were changed regularly. But secret codes are never secret forever. Any code that man devises, others can decipher. Codes are still viable because most codes can take weeks or months, and sometimes even years of effort by highly skilled people to figure them out. Since the volume of coded messages is huge, and there are simply few people who have a knack for breaking codes, your codes are unlikely to be broken in time to hurt you.
Due to a set of fortuitous circumstances, the British were able to get a head start on breaking German codes, and then followed this up by developing advanced (for the early 1940s) technology to rapidly break the German codes. The "fortuitous circumstances" began in the late 1930s, when the Polish secret service managed to obtain one of the German code machines (it was basically a typewriter, with a "code wheel" and other electronics built in) and, most importantly, had a mathematician on hand who was able to figure out how the machine worked. The Poles did not share this information with Britain or France since they did not want to risk a leak which would antagonize the Germans. However, during 1939, the Germans made it clear that they were likely to invade Poland. So the Poles approached Britain and France and rather shocked the code experts from these nations with the extent to which Poland had cracked the "unbreakable" German ciphers. The Poles passed on their knowledge to the British before the Germans conquered Poland.
The Germans called their code machine "Enigma," and Polish experts had already figured out a lot about Enigma before they passed the torch to the British. The Poles had discovered that Enigma codes could be broken, and developed techniques that allowed this to be done quickly enough to be of use. This speed was of vital importance, as the problem with breaking codes is that you had to decode a great many messages before you got a general sense of what the enemy was up to. And you had to break these codes quickly, otherwise you were merely studying what the enemy had done, rather than what he was about to do. While reading "old" messages was of some use, it was not nearly as decisive as reading current stuff.
In practical terms, the Enigma codes could not be broken, with the Germans calculating that conventional decrypting methods would require millions of man years to decipher their messages. In theory, they were correct, but what can be done can be undone. In the case of the Polish cipher experts, Enigma was undone at high speed. The Poles took advantage of the tendency of the Germans to begin many types of messages with the same words, and this proved a sufficient hook for a clever Polish mathematician to find a means to take apart the Enigma ciphers. Having one of the Enigma machines completed the "keys" the Poles developed to unlock Enigma.
Although the Polish techniques were adequate in 1939, the Germans continued to enhance the complexity of their Enigma system. Earlier additions to the Enigma system had driven the Poles to come up with ever more equally clever techniques to keep up with the German cipher efforts. But eventually much more powerful methods were required. The British found a novel solution by building one of the first modern computer. Although more mechanical than electrical, the machine was built for the sole purpose of speeding up the breaking of German codes. It wasn't much of a computer by modern standards, but it was much faster at processing complex data than humans and could be run round the clock. While human decoders did the delicate stuff, the computer was able to apply the brute force calculation needed to finish the decoding.
The Germans knew that they could lose some Enigma machines to capture (as some were), as well as the seizure of code wheels and code books. What the Germans never realized was how thoroughly the Allies understood the Enigma machine, and how much mental effort Allied specialists applied to developing ways to make Enigma codes easier to decipher.
Although the Germans would change code wheels periodically, and thus slowed down ULTRA, the Germans never realized that a technique had been developed to regularly break the new codes. If they had suspected the extent of the Allied effort, they would have developed a new coding machine which the Allies might never (or at least not quickly enough) get their hands on and find a way to decipher. ULTRA's formidable resources could still have been brought to bear, but much time (a year or more) would be lost.
But as a practical matter, it would have been very difficult for the Germans to introduce a new code machine during the war. To do so would have required the rapid deployment of thousands of new machines, the simultaneous training of operators and subsequent disruptions to all their operations. The Germans did not want to do this, and this added to their desire to believe that Enigma was secure.
The deception that ULTRA made possible had to be handled very carefully, lest it become known to the Germans. There were many Germans who DID suspect that their codes were broken, but as long as the senior German commanders still believed that the Enigma codes were secure, the Allied deception could continue.
The Allies maintained very tight security around their code breaking operation, and no one outside the ULTRA personnel or the most senior political and military commanders even knew ULTRA existed. Information gleaned from ULTRA was carefully passed to Allied commanders, who were simply told that it was obtained via the usual intelligence gathering operations. Allied generals and admirals came to depend on these visits from higher headquarters. But, except in a few cases, they did not become overly dependent on the ULTRA information. The one exception was the naval forces. The war against the German submarines ("U-boats") was a desperate affair until the Summer of 1943, and ULTRA information played a large role in locating German subs so that convoys could avoid them, or Allied ships and planes could go after the U-boats.
The German navy (Kriegsmarine) was more security conscious than the army (Wehrmacht) or air force (Luftwaffe). Although all three services used the same Enigma machine, the navy used all its features, even though this made more work for the operators. The Kriegsmarine's greater security consciousness arose from the fact that they were more dependent on radio transmissions than the Wehrmacht or Luftwaffe. The army and air force could use telephones to contact most of their troops, the navy could not. German submarines had to use radios, and had to be careful with sending messages lest nearby Allied aircraft and ships use radio direction finding equipment to locate the U-boats. The Allies let it be known that their radio direction finding equipment was first rate and constantly being improved. This was the deception to prevent the Kriegsmarine commanders from realizing that Enigma was being deciphered. But using extra code wheels and other optional features of Enigma made the Kriegsmarine codes harder to crack. Fortunately, the Allies were able to capture navy Enigma machines several times during the war and thus were able to keep up with the new twists the German navy added to Enigma use. Subs, weather ships and other warships were a source of captured Enigma machines and code books. Between the primitive computers crunching away, the Allied cryptanalysts burning the midnight oil and a steady supply of captured Enigma equipment, enough Kriegsmarine messages were broken quickly to win the U-boat war before Britain was isolated.
Thus armed with German orders transmitted to their U-boats, the German wolfpacks (groups of U-boats organized for mass attacks) regularly found Allied convoys suddenly taking wide detours. Worse, Allied aircraft increasingly came out of nowhere to sink U-boats that thought they were off the beaten track. The German admirals blamed all this on Allied radio direction finding, airborne radar, masses of anti-submarine ships and aircraft and the fortunes of war. Some German officers blamed all this on traitors.
The Allies knew that the Germans would suspect that Allied spies and German traitors were causing all these leaks. Therefore, an additional, and crucial, deception was run by the Allies to keep the Germans from figuring out that Enigma had been compromised. The Allies made a big deal of all their "spies" within the German armed forces and government. This was a bonus during the ULTRA deception, as the Germans saw ample evidence of the Allies knowing Nazi plans. Spies within Germany were a likely source, especially since the senior Nazis were a suspicious bunch to begin with. But in reality, there were not that many Allied spies within Germany. The Nazi secret police was rather efficient, and very ruthless. Many loyal Germans were caught in the Gestapo (secret police) efforts to root out the sources of all the information the Germans were getting.
The German high command never suspected ULTRA existed, nor did they see through the many deceptions that flowed from Allied code breaking efforts. Indeed, ULTRA was not publicly revealed until the 1970s.
Incident at Cherbourg
On June 28, 1944, Cdr. Quentin R. Walsh, U.S.C.G., was leading a party of armed Coastguardsmen on a reconnaissance to determine the extent to which the Germans had damaged the port facilities at Cherbourg before surrendering the city. They came across a German sailor, whom they promptly captured. The man informed them that about 50 American soldiers were being held prisoner in one of the harbor forts, guarded by some German troops who had refused to surrender.
Accompanied by another officer, Walsh approached the fort and called for a parley. A German officer escorted the pair into the fort, where they confronted the German commander. They reminded him that his direct superiors had already surrendered Cherbourg, and that he had an obligation to obey their orders. The German officer flatly refused to surrender, informing Walsh that he and his men would fight to the death. Walsh quietly told him that there were 800 American troops men outside, ready to take the fort by storm if necessary. Hearing this the German commander suddenly lost interest in a glorious death for Führer and fatherland, and agreed to surrender.
The German officer must have felt pretty stupid when he discovered that Commander Walsh actually had only seven armed men waiting outside.