Non-intervention in the Spanish Civil War
During the Spanish Civil War, most European countries followed a policy of non-intervention to avoid potential escalation or expansion of the war to other states. This policy led to the signing of the Non-Intervention Agreement in August 1936 and the setting up of the Non-Intervention Committee, which first met in September.
Source: Wikipedia — Non-intervention in the Spanish Civil War (CC BY-SA 4.0)