In an attempt to prevent future wars, the international community established the League of Nations in 1920. Switzerland held a referendum on membership, which was accepted by a wafer-thin majority. The seat of the League was in Geneva.

The inter-war period saw the rise of competing political ideologies, communism and fascism, offering radically new concepts of society. Fear of the former, embodied by the USSR, partly shaped reactions to the latter, embodied first in Italy, and later - more aggressively - in Germany. For many people communism was more repugnant than nazism.

Swiss foreign policy in the 1930s tended to ignore the threat posed by the fascist powers. Thus it failed to condemn Italy's invasion of Abyssinia (Ethiopia) in 1935 or to impose the sanctions demanded by the League of Nations and accepted without objection Hitler's annexation of Austria in 1938.

At the same time, it refused to recognise the USSR.