OKH, Gen. Staff of the Army, Operations Division (I), 1st Presentation of Sketch of Attack against Switzerland, June 25, 1940, signed von Menges.
BA-MA, RH 2/465:Schweiz, Bd. C.
Op. Div. (I)
June 25, 1940
Secret Command Matter
Only by Officer!
1. ) Order Received:
The possibilities concerning a surprise invasion of Switzerland by German troops from France and Germany are to be explored in brief, under the condition that Italian troops will simultaneously attack Switzerland from the south.
2. ) Execution:
In this enterprise it is imperative to achieve the following by a quick surprise invasion from several directions:
1. ) Destruction of the enemy army in such a manner that a unified command and a build-up of further resistance of individual lines and an orderly escape into difficult mountain terrain (thus delaying the outcome of the war) is prevented.
2. ) For political and morale reasons the rapid and undamaged occupation of the Capital and the region of the weapons industry around Solothurn.
3. ) To gain the most important rail and road junctions as well as the numerous bridges in an undamaged state so that the country may be used as soon as possible as a transit area to Southern France for all transports.
Apart from 9 border guard brigades (about 100 battalions), Switzerland has 6 infantry divisions, 3 mountain divisions, 3 mountain brigades and, as corps troops, 3 light brigades. Added to this are 75 battalions of "territorial forces" (a type of riflemen). There are no armored units. The air force is weak, modernized only to a small extent; the antiaircraft forces in the initial stage of build-up.
According to the available reports, (5-7 divisions are deployed along the borders of the north and northeast. Only 1 1/2 divisions are at the French border (unless more forces are being shifted there now), the rest in the south and southeast.
The enemy has no way of going on the attack due to the necessity of protecting his long borders. He will defend his fortified positions near the border. The weakness of his current positioning is along the French border. A possible repositioning to that region can occur only at the expense of safeguarding the German border.
After losing his positions near the border, the enemy will try to regroup on a line Lake Geneva-Lake Neuchâtel-Lake Biel-Olten-Zurich-Sargans.
3. ) Fortifications of Switzerland:
Emphasis on reinforcement in the sector Basel-Constance-Rheineek-Sargans. Light reinforcement, only a few places medium reinforcement. Heavy reinforcement of the cornerstones Rheineck and Sargans, in between steep mountain slopes. Only weak safeguarding along southern shore of Lake Constance.
Thirteen Rhine bridges between Constance and Basel. Weaker points southwest of Basel, eastward to Waldshut and near Eglisau. Rear positions: Apparently so far only barricade fortifications in narrow sections of valleys. Reinforcement planned for line Olten-Aarau-Zurich-Sargans.
Reinforcement starting only early 1940, first only barricades at individual places and field-like firing positions.
Weak points of position: Around and west of Nyon, east of Pontarlier, north of La Chaux-de-Fonds; roads of mountain passes north and south of St. Maurice not fortified. Rear positions between the lake narrows have not yet been reinforced.
c) Details: The shooting ranges are 6-8 m above ground, thus a good target; nothing known about antitank ditches. Everywhere road barricades are to be expected (prepared concrete blocks, to be overcome by blasting or by prepared bridging structures). Border guard houses without combat value.
4. ) Own Forces: See Map.
Use of Forces:
In this plan, motorized and tank divisions are envisioned for the rapid occupation of Bern, Lucerne, and Zurich and the blocking of the enemy's roads of retreat leading south, the few available mountain divisions only as far as absolutely necessary, infantry division for breaking through fortification line and for reaching the more nearby targets.
Use of a motorized instead of mountain division through Savoy Alps (= the southern most column in the Rhône valley) should be considered in spite of the difficult terrain in the second part. Attack from the east should be avoided due to the difficult mountain terrain and the strong enemy fortifications.
For the infantry division deployed through Constance, the car ferry Friedrichshafen-Romanshorn might be used for the surprise landing of partial units for opening the fortifications from the south, while simultaneously using assault boats.
In case enemy defense measures still permit, airborne landings around Bern and, for the opening of the mountain exits from the south, of airborne troops around Olten and Solothurn should be undertaken, possibly also later to seal off retreat roads in southeastern Switzerland. The occupation of the point around Chur-Davos should be left to the Italians due to the difficult terrain.
One Army Supreme Command, 4 army corps (high number needed for reasons of terrain), 3 infantry divisions, 3 motorized divisions, 1 armored division, 2 mountain divisions = 9 divisions.
In southern Germany camouflaged for training purposes; in France some units at a distance, as motorization permits rapid transfer.
d) Time required for deployment cannot be predicted at this time due to current positioning.
e) Time required for operation: Occupation of Zurich, Lucerne, and Bern has to be possible no later than during the second day.
5. ) Tactical Command:
Make use of the experience in Norway: Assignment of tanks, guns, and individual motorized troops to the vanguard; use of the mountain equipment of 7th Army; reinforcement of marching troops by machine gun company (motorized); increased use of infantry guns and grenade throwers; formation of strong advance units using the vehicles of the antitank gunner units, here not so necessary for antitank defense.
6. ) Details:
Secrecy and Deception:
Discreet, increased closing of Swiss border. Corresponding press notices. Deceptive radio messages and radio silence for individual parts.
b) Use of spies to explore details of fortifications. What is the situation at rear positions? Are regroupings along the French border under way?
c) Improvement of the particularly bad maps. Production of maps 1:100,000. Acquisition of maps about road conditions, as much as possible on the open market in Switzerland. Preparation of a condensed military-geographical description of the country.
d) The chief of transports must be listened to about his requirements for deployment and about specially important, and thus rapidly to be occupied, traffic routes in Switzerland.
e) The use of forces west and south of Lake Geneva demands a shifting of the demarcation line as soon as possible, in order not to alert Switzerland too early of our intentions.
f) Given the momentary political situation in Switzerland it is possible that it might accede peacefully to our ultimatum demands, so that after a warlike crossing of the border a rapid transition to a peaceful invasion must be assured.
Captain of the General Staff