During World War II, detailed invasion plans were drawn up by the Germans, but Switzerland was never attacked. Switzerland was able to remain independent through a combination of military deterrence, economic concessions to Germany, and good fortune as larger events during the war delayed an invasion.

Attempts by Switzerland's small Nazi party to cause an Anschluss (annexation) with Germany failed miserably. The Swiss press vigorously criticised the Third Reich, often infuriating its leadership. Under General Henri Guisan, a massive mobilisation of militia forces was ordered.