The sheer size of Europe's neutral club prevents us from offering a fully comprehensive survey within the confines of a single volume. Regrettably certain countries that could qualify as neutrals or non-belligerents have been omitted. In terms of its impact on the war, the ‘neutrality’ of the Soviet Union and United States before 22 June and 7 December 1941 respectively was of course of enormous significance. Historians have studied the attitudes of both exhaustively and there is little benefit in rehearsing their findings in the present survey. Despite America's fervent attachment to its neutrality acts, the actions of both countries were ultimately guided less by concepts of neutrality than by considerations of their Great Power status and resources. Neither went out of their way to assist Europe's neutrals, even although most states tried to court American support during the Phoney War.

As its foreign relations were handled by Denmark, Iceland was covered by Copenhagen's declaration of neutrality on 3 September 1939. Reykjavik promptly declared its temporary independence from Denmark after the German occupation on 9 April 1940, since it was clear that Denmark's continued claim to ‘neutrality’ would find few takers in London, in whose hands Iceland's fate ultimately lay. The ploy did not succeed and the following month British troops landed at Reykjavik in order to compensate Britain for the loss of Norway and pre-empt any possible German action against the country. Finland's neutrality lasted barely two months, brought to an end by Russia's attack on 30 November 1939.