Swiss and the Nazis

by Stephen Halbrook

  The first plan was Operationsentwurf Schweiz—Tannenbaum (Draft Operations plan Switzerland—Christmas Tree). It was submitted for consideration by General Wilhelm Ritter von Leeb of Army Group C on October 4 in response to the August 26 directive from General Halder of the General Staff’s Operations Section.62

  The objectives of Operation Tannenbaum are clear in the plan’s Map 1, reproduced in this book (see photo section).63 Another map shows the positions in France and Germany of motorized and panzer forces and their routes from these positions to get to the Swiss border.64

  The essence of the attack was succinctly worded: “Concentrated surprise penetration from Lake Geneva to Lake Constance toward the center of the country with strong and fast outer wings…. We must force the quick subjugation of Switzerland by using extremely superior forces.” The offensive would sweep over all the entire borders with Germany and France. However, the plan began by warning of the defensible terrain even in the non-Alpine areas:

  The shortest way into the politically and militarily vital area of the country (region encompassing Bern, Lucerne, Zurich, Solothurn) leads from the Waldshut area in the north to [the east of] Lake Neuchâtel. What speaks against putting the emphasis on this front are (1) the Jura, which offers difficult access and can be defended with weak forces, (2) the existence of the Aare stronghold position between Lake Neuchâtel and Aarau behind it, (3) the difficulties of concentrating and striking through the Black Forest between Basel and Waldshut, and finally (4) the potential of driving the enemy toward the south and the high Alps.

  Of course, the “shortest way” as the crow flies was directly from Germany. It was not the easiest way for Wehrmacht troops because it led through the treacherous Jura mountains and across the steep-banked Aare River. The takeoff area on the German side was hilly as well. The approaches from newly occupied France in the west, however, were a different story. From the west, there would be swift breakthrough attacks by panzers, motorized and mountain divisions, and infantry on all roads between Geneva and Basel. The timetable depended on “whether the surprise element succeeds and on the fights in mountainous terrain that we must expect.”

  Coordinated assaults through the upper Rhone and Rhine valleys would sow panic, hitting the Swiss on their exposed flanks as they attempted to withdraw back from the northern plain toward the high Alps. A simultaneous Italian assault was proposed. “To tie up enemy forces, an Italian attack on all mountain passes to the upper Rhone and Rhine valleys will be desirable. Most important, however, strong Italian forces must advance over the St. Bernhard and Simplon passes to support our own advances through the upper Rhone Valley.”

  Stiff resistance was expected. “individual task forces will get involved in many battles. Our horse-drawn medium artillery will be necessary but in many cases will find it hard to get through the difficult terrain.” in preparation for the attack, the entire Swiss border must be sealed to prevent communications and cross-border movements. Disinformation and subterfuge were to be used, so as to “deceive the Swiss with friendly reports about Switzerland in the German press and with economic concessions.” To minimize Swiss alarm over buildups of Wehrmacht troops close to the border, “aggravate relations with France, either in connection with the noncompliance with armistice conditions or for other appropriate reasons, as a way of explaining the assembly of motorized units.”

  After review, Operations Division IIa directed a revision of the plan on October 9. The General Staff added the following comments:

  1.) The allocation of forces is very high and probably exceeds the required forces considerably.

  The 21 German divisions planned are opposed by the following on the Swiss side:

  9 infantry divisions

  3 mountain brigades

  1 combined light division.

  2.) Despite division of the attack into two prongs, the surprise element is at risk

  a) because of the large allocation of troops

  b) in particular because of Group E, the assembly of which in Vorarlberg cannot be hidden.

  3.) The deployment of two army headquarters is a consequence of the high allocation of forces. It is not desirable because the operation can be led by one army headquarters….

  4.) The Operational Division is of the opinion that

  a) Group E (Vorarlberg) should be eliminated. An effective feint can be accomplished with far fewer troops.

  b) The second prong is to be eliminated entirely.

  c) in Group D (Waldshut–Lake Constance) the following will suffice:

  1 panzer division

  1 motorized infantry division

  1 infantry division.65

  From the above, the initial revisions of this plan reduced the number of divisions deployed from 21 to 11. There were many uncertainties, and German resources were not infinite. No further documents on Operation Tannenbaum could be found. Hitler had made the fateful decision to attack Russia in the spring. This may have been part of the reason the whole Tannenbaum operation was cancelled abruptly on November 11, 1940, by a telephone call by Captain Worgtzky of the General Staff: “The Operations Division is reporting to the Army Group that plan ‘Tannenbaum’ is no longer relevant because it has been overtaken by events.” This was relayed to the head of the General Staff.66 The detailed planning, however, provides clear evidence that an invasion of Switzerland came within a hair’s breadth of execution. Had the order been given, the course of the war in 1941 and after might have been significantly different.

  Also, combat planning inevitably contains an element of chance, in part because both sides cloak their preparations in secrecy, in part because of the unpredictable impact of events. In any case, a second invasion plan, independent of Tannenbaum, was presented on the same date as the original Tannenbaum, October 4. General Staff Major Bobo Zimmermann submitted a detailed battle plan to Armeeoberkommando 1 (OAk 1, the High Command of the First Army) entitled “Studie über einen Aufmarsch gegen die Schweiz aus dem Raume der 1. Armee” (Study over a Deployment Against Switzerland from the zone of the First Army).67

  The opening line of the Zimmerman plan stated the obvious: “The defeat of France has fundamentally changed the military-political situation of Switzerland.” Swiss defenses anticipated an attack from the north and northeast—i.e., Germany and Austria—and therefore were concentrated on the general front of Basel–Bodensee–Sargans where they were buttressed with strong permanent fortifications. The border with France, the Geneva–Jura–Basel line, was poorly fortified since the Swiss felt no threat from France. As a result of the strategic change, the whole northern front of Swiss defenses was now exposed and vulnerable from the west and the rear.

  Zimmerman knew the Swiss realized their predicament and were busy attempting to fortify the western and northwestern fronts. He also referred to a map purporting to show the Central Redoubt, the very defensible Alpine terrain, but noted that “details are still missing.” The Germans of course were well aware that an Alpine redoubt would likely be the main focus of any last stand by Swiss forces. The fact that they had not obtained the specifics is a compliment to Swiss military secrecy. They did see that defenses in the Jura mountains were being reinforced, and also knew the Swiss were prepared to destroy bridges, tunnels, and highway choke points.

  In Zimmerman’s plan, the First Army would be deployed against Switzerland’s northwest border. It would break through to cut off any retreat to the Alpine Redoubt. The basic thrust of the operation would be to split the mass of the Swiss army in such manner as to block the important valleys which lead from the northwest and north up into the Alps. It warned emphatically: “No operation into the Alps!” German troops would only be tied down and wasted there—as they would soon be in the Balkans, owing to the Yugoslav and Greek resistance continuing even after a formal surrender.

  The operation would be difficult and require extensive preparation, utmost secrecy and assaults with maximum speed. It would be launched from two starting points, the southern one
being the main thrust. The lightning strike must overcome the difficulties of the Jura barriers and terrain, seize the land bridge between the Lakes of Geneva and Neuenburg, and push through the narrow passage between the Neuenburg and Biel Lakes.

  The Zimmerman plan included and examined a French militarygeographical description of Switzerland, apparently one of the many documents that fell into German hands at la Charité.68 The plan notes that over the 200-kilometer French-Swiss border from Geneva to Basel there were only 6 railroads and 14 major roads, which if destroyed could not be quickly rebuilt. The plan, relying on Michelin maps and observations from reconnaissance, went into great detail about the hazards of breaking through the Jura, which was also entirely dependent on the season—the Jura’s summer is short. Attack from May through October was best. Winter would be possible but dangerously slow, although the report notes that snowplows were available in France. Zimmerman seemed to have no inkling of Hitler’s designs on Russia.

  The whole operation was based on current Wehrmacht troop dispositions and transportation resources, showing that it was very much an “active” plan, not just a theoretical study. The buildup would be carefully camouflaged, with troops being moved to their attack lines via several circuitous routes over two and a half days.

  Current Swiss force levels were estimated at 125,000 on active duty, but the plan noted: “There is no doubt that the entire Swiss Army could be under arms in these days of tension. We should therefore expect to face the entire Swiss Army.”69 After analyzing specific Swiss units which the Wehrmacht would encounter, Zimmermann wrote:

  The Swiss Army has fighting power and spirit, especially in that they are defending their own country. The army makes good use of terrain and is very skilled in guerrilla warfare. Swiss soldiers have considerable technical skills. We would therefore run into tough resistance, though we would probably not have to worry about major coordinated counterattacks.

  The key to success was lightning-fast operations. The breakthrough in the Jura must take place before the roads could be destroyed, and panzers must push through between the Lakes of Geneva and Neuenburg. The Luftwaffe was obviously superior to the Swiss Air Force and could be, if necessary, supplemented with units of the Italian Air Force. With control of the air, paratroopers could be dropped behind Swiss lines to seize bridges, tunnels, and other critical points.

  In a cover letter Zimmermann listed several attachments—maps of roads over Switzerland’s northwest border, Swiss fortifications, details of the areas around Lake of Geneva and the Rhone valley, and specified Michelin maps.70 Of special interest was a study by General Staff Captain Reinhardt focusing on sabotage of the Swiss railway system to prevent its use for troop movements. Since many Swiss trains were no longer powered by steam but by electricity, destruction of the power stations and grid components could prevent the Swiss from using their railroads to meet a German attack or to pull back into the Swiss Alps. The study details the specific rail lines to be disrupted consistent with the Wehrmacht attack points.71

  By the second week of October, Zimmerman’s plans seemed to have support at high levels. The Swiss clearly were worried. An October 11 intelligence report indicated: “Because of a successful sabotage attack on the railroad tracks between Annecy and la Roche, the Swiss government has now prohibited the export of Orlikon weapons as a concession to the Germans in hopes of avoiding invasion. They had been shipped to England via lisbon.”72

  Actually, Hitler had ordered the destruction of the la Roche-Annecy rail line in unoccupied France—a critical rail connection between Switzerland and Upper Savoy—in June, just after France capitulated, but the order could not be carried out then.73 The Swiss firm Orlikon-Bührle had exported thousands of 20-mm antiaircraft cannon to France and England as long as it could. After France fell, the firm managed to smuggle the blueprints to England, which would produce 35,000 cannon; the United States would make 150,000 of them for her navy. Once Switzerland was encircled, the government entered into agreements to export the cannon to Germany74—as with all such exports, in exchange for goods necessary to survive and defend against Germany.

  Despite the danger, German agents continued to report that the Swiss favored the Allies. “propaganda against the Reich” was the subject of an OKW analysis which explained Swiss “neutrality” as follows:

  We have reports that a brigade commander of the Swiss Army made the following statement to his officers: “it is our task to remain steadfast and firm as a rock. We must hope that England will do the same. Then Nazi Germany will certainly be defeated. You must meet any defeatism with vigor. You must make it clear to our officers and troops that the Swiss Army can absolutely hold its ground against the German Army. Only dive-bombers and tanks of the German Army are highly developed, and both are instruments of combat which are useless in the high Alps. Switzerland today is so well armed that we are absolutely capable of victoriously opposing the Nazis on our territory. The only tool that we are missing is airplanes. But i am certain that in case of need we would get those immediately from the Royal Air Force.”

  The common opinion was that Switzerland would fiercely resist any attack by German troops, even to the point of destroying its own infrastructure. In the event of an invasion, bridges, roads and tunnels in the Alps would be blown up to prevent the Axis from using them.75 Even the Germans realized they could do little to stop such events.

  The possibility of getting air support from the RAF was about as likely as the poles getting RAF fighters to save Warsaw in 1939. Yet, the determination expressed above was more than just bracing talk for the troops. The Germans knew they would have to suffer heavy losses for an uncertain prize. An OKW report noted that “the general attitude of the population remains the same. The population’s hopes are winter and America. People are purposely trying to downplay German successes and war actions.” The Swiss went so far as to eliminate the screaming sounds of Luftwaffe dive-bombers in German newsreels “so as to avoid undermining the population’s will of resistance.”76

  The United States was far away. While the Swiss knew the Germans would not likely risk an attack during the treacherous winter months, in those dark days in the late fall of 1940 there was hardly a glimmer of hope for American intervention in Europe.

  Elsewhere forces of the Reich were overwhelmingly successful. As Hitler was digesting his triumphs, the OKW griped on November 15 that “lately the mood in Zurich is more anti-German.” The Swiss believed that the Italians would be a moderating influence on German demands. In fact an article in an Italian newspaper had “suggested that Switzerland should remain an independent country. People are also of the opinion that Mussolini would not allow Germany to attack Switzerland.”77 However, Mussolini had already discussed the carving up of Switzerland with Hitler,78 not to mention that the bombastic but ineffectual Duce was in no position to dispute German strategy.

  The Axis was in a position to put Switzerland in an economic stranglehold. Switzerland had no coal or fuel resources. Germany was rich in coal—in fact one of the few materials of war which it possessed internally and used as leverage. The Reich declined Switzerland’s proposal to pay for coal deliveries in gold and demanded a barter exchange. Germany was able to set the terms, since Switzerland had no alternative. Despite the cold, hotels were limited to using small electric heaters. Some Swiss either left the country or moved south. According to a November 1940 OKW report:

  Many rich Jews are said to be departing Switzerland or trying to sell their real estate at any price. The result is that real estate prices have been sinking drastically. There are apparently Swiss citizens who are moving their companies and their residence to southern Switzerland. They prefer to be annexed by Italy instead of Ger many in case Switzerland is divided up.79

  OKW intelligence further reported that “in order to be prepared for all eventualities, the Swiss government has ordered all families to obtain supplies that will allow them to completely support themselves for two months.” Such officially sa
nctioned hoarding ensured that supplies would be adequate and would discourage panic buying. There was a rumor, spread by a business, that soap would run out, but there was no run on soap because everyone already had sufficient supplies. “Some people apparently have sufficient supplies of everything for three years.” The German report continued:

  The government stores large amounts of supplies. Apparently wheat and gasoline are stored by putting huge tanks filled with wheat or gasoline into Swiss Lakes (Lake Lucerne) to protect them from bombs. It is said that these tanks are lifted from time to time and their contents checked. The import of goods from abroad, in particular from overseas, has apparently been halted almost completely. All ships loaded with goods for Switzerland are said to be stopped now in Gibraltar.80

  These preparations by the population were factors the Germans needed to consider in assessing the extent to which the Swiss could withstand an invasion. Under the heading “Swiss Views about the possibility of a German Attack,” an agent reported on December 2 that the Swiss people knew the Germans did not want to risk the crucial rail links to Italy:

  There are roadblocks, barbed wire entanglements and bunkers all along the line between Basel and Zurich. But currently there is no fear that the Germans will attack. The Swiss are saying that Germany absolutely needs the Gotthard and Simplon tunnels to provide Italy with supplies. In the case of a German attack, the Swiss hope that they would be able to either hold or destroy those two tunnels. They believe that the damage inflicted on the Axis by this act would be greater than any gain from an occupation of the country. However, the Swiss also think that Germany could cause great economic difficulties for Switzerland and that Switzerland therefore must show consideration for Germany.81