What European countries were not involved in World War 2?

There were several. Switzerland - Despite being surrounded by Axis nations and territory (but with few natural resources, no vital trade routes, no naval bases) the Axis nations left her alone. The two sides did trade frequently as Switzerland required natural resources to keep her industries alive. Sweden - Traded freely with Germany providing iron ore and some manufactured goods such as ball bearings. Turkey - Did declare war on Germany a few weeks before the end of fighting (always a nice touch) but during the major portions of the war traded freely providing Germany with her indispensible requirements of chromium ore. Spain - Despite owing the Axis for support during their '30s civil war, the Spanish never got into WWII. They did provide some support for German naval forces at various times. Spain also provided tungsten ore to the Axis nations. Portugal - I think they pulled a 'turkey' and declared war at the end of hostilities against Germany. Ireland - Despite being ravaged by the English for centuries, the Irish never aided the Axis, probably since to do so would have meant even more brutalization at the hands of the English, Germany being in no position to assist them.