Nearly all of the countries involved in World War II chose to align with one of two massive international alliances: the Hitler-led Axis Powers or the Allies, which eventually evolved into the modern United Nations. However, not every country chose a side—at least not overtly. A handful of states, known as neutral powers, chose not to ally with either side during the war. These nations took a neutral position in an attempt to avoid being attacked, invaded, and/or occupied.
This strategy often failed. For example, Denmark, Belgium, Norway, Luxembourg, and the Netherlands had all established policies of neutrality prior to the start of the war. Yet, Germany ignored these intentions and invaded all five countries on April 9-10, 1940. Soon after, the Soviet Union forced the theoretically neutral nations Lithuania, Estonia, and Latvia into treaties that led to the Soviets occupying and ultimately annexing all three countries. Once occupied, many countries were forced to cede control of their trade partnerships, territory, resources, and military bases to their occupiers, even to the point of allowing their citizens to be conscripted as soldiers in their occupiers' armies.
Countries that Remained Neutral During World War II:
- San Marino
- Saudi Arabia
- Vatican City
Official neutrality often meant unofficial favoritism
Most nations that declared their neutrality still helped or rallied behind one side or the other. Portugal, Sweden, and Switzerland all helped the Allies by providing brigades of volunteer-only soldiers, and Sweden helped the Allies crack a secret German code. Spain, Sweden, Portugal, Switzerland, and Turkey all sold raw materials to the Axis powers during that same time, and Sweden allowed Nazi troops free passage through its territory. Argentina, Sweden, and Switzerland, in fact, were three of only a handful of countries that managed to support both the Axis and the Allies in various ways.
The United States also declared its neutrality at the beginning of the war, and managed to remain neutral for more than two years while also finding creative ways to funnel supplies, ammunition, and even planes and warships to Great Britain and its allies. Eventually, however, the attack on Pearl Harbor in 1941 forced the United States to retract its neutrality and officially enter the war.