The concept of collective defence in Europe emerged almost simultaneously with the start of European integration. In the background of devastation caused by World War II, an ambitious idea quickly emerged: to unite European states that were still recovering from the conflict and work together to ensure security and maintain peace.
The idea of collective defence, which was perceived as revolutionary at that time, became the basis for the first post-war international agreements aimed at the prevention of new wars in Europe. In March 1947, France and the United Kingdom signed the Treaty of Alliance and Mutual Assistance in Dunkirk, in which they pledged to work closely with each other and with other UN Member States to preserve peace and deter aggression, especially on Germany’s side.
