Foreign involvement in the Spanish Civil War

The Spanish Civil War had large numbers of non-Spanish citizens participating in combat and advisory positions. The governments of Germany, Italy—and to a lesser extent Portugal—contributed money, munitions, manpower and support to Nationalist forces led by Francisco Franco. The government of the Soviet Union, and to a lesser extent France and Mexico, likewise aided the Republicans (Loyalists) of the Second Spanish Republic. The aid came even after all the European powers had signed a Non-Intervention Agreement in 1936. While individual sympathy for the plight of the Spanish Republic was widespread in the liberal democracies, pacifism and the fear of another world war prevented them from selling or giving arms. The Nationalist pleas meanwhile were answered within days by Hitler and Mussolini.

Non-intervention had been proposed in a joint diplomatic initiative by the governments of France and the United Kingdom, responding to antiwar sentiment. France was also worried that the civil war in Spain might spread to France. It was part of a policy aimed at preventing a proxy war, and escalation of the war into a major pan-European conflict.

On 3 August 1936, Charles de Chambrun presented the French government's non-intervention plan; Galeazzo Ciano promised to study it. The British, however, accepted the plan in principle immediately. The following day, it was put to Nazi Germany by André François-Poncet. The German position was that such a declaration was not needed. A similar approach was made to the Soviet Union. On 6 August, Ciano confirmed Italian support in principle. The Soviet government similarly agreed in principle, so long as Portugal was included, and that Germany and Italy stop aid immediately. On 7 August, France unilaterally declared non-intervention. Draft declarations had been put to German and Italian governments. Such a declaration had already been accepted by the United Kingdom, Belgium, the Netherlands, Poland, Czechoslovakia and the Soviet Union, renouncing all traffic in war materiel, direct or indirect. The Portuguese Foreign Minister, Armindo Monteiro, was also asked to accept, but held his hand. On 9 August, French exports were suspended. Portugal accepted the pact on 13 August, unless her border was threatened by the war.

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