Neutral powers during World War II

•  Estonia – Estonia, along with its Baltic neighbours Lithuania and Latvia, jointly declared their neutrality on 18 November 1938, in Riga, at the Conference of Baltic Foreign Ministers with their respective parliaments passing neutrality laws later that year.[1] Despite that, all three Baltic states were occupied twice by the Soviet Union and once by Nazi Germany.

•  Iceland – Occupied by Allied forces from May 1940.

•  Ireland – The policy of Irish neutrality during World War II was adopted by the Oireachtas (Irish Parliament) at the instigation of Éamon de Valera, the Taoiseach (head of government) upon the outbreak of hostilities in Europe. It was maintained throughout the conflict, in spite of several German air raids and attacks on Ireland's shipping fleet by both Allies and Axis. De Valera refrained from joining either the Allies or Axis powers

•  Latvia – Latvia, along with its neighbours Lithuania and Estonia, jointly declared their neutrality on 18 November 1938, in Riga, at the Conference of Baltic Foreign Ministers with their respective parliaments passing neutrality laws later that year.[2] Despite that, all three Baltic states were occupied twice by the Soviet Union and once by Nazi Germany.

•  Lithuania – Lithuania, along with its neighbours Latvia and Estonia, jointly declared their neutrality on 18 November 1938, in Riga, at the Conference of Baltic Foreign Ministers with their respective parliaments passing neutrality laws later that year.[3] Despite that, all three Baltic states were occupied twice by the Soviet Union and once by Nazi Germany.

•  Portugal – Portugal was officially neutral during World War II. However, it maintained a close relationship with the UK, due to the alliance it had for the last six hundred years, which is the longest lasting military alliance in history. The Estado Novo sought neutrality in order to keep Spain neutral and prevent it from joining the Axis. Portugal allowed the United States to use a secret military base at Santa Maria Airport in the Azores through a military agreement signed on 28 November 1944. This violated its neutrality and rendered Portugal as a non-belligerent on the Allied side.

Colonies of Portugal:

• Angola
• Cape Verde
• Portuguese Guinea
• Portuguese India
• Macau
• Mozambique
• São Tomé and Príncipe
• Portuguese Timor (Occupied by Japan from 1942 to 1945)

Meeting at Hendaye between Franco and Hitler in October 1940.

 Spain Initially holding to formal neutrality, once Italy entered the war in June 1940 Francisco Franco switched Spain to the status of "non-belligerent" and proceeded to occupy Tangiers. From June 1940 onward, and until February 1941, the Francoist regime was greatly tempted to interventionism. Prominent Germanophile Ramón Serrano Suñer had great ascendancy in the government.[4] However, meetings with German officials, including the meeting between Franco and Hitler in Hendaye on 23 October 1940, did not bring formal entry of Spain into the war.

Operation Barbarossa removed the Mediterranean from the main theatre of war, causing a decline in Spain's interest in intervention. A decreasingly relevant Serrano Suñer was still able to create the Blue Division,[5] of volunteers to fight for the Axis. With the conflict decidedly turning towards the Allies, on 1 October 1943 Franco returned the status of Spain to one of "vigilant neutrality".[6]

Spain was a key provider of tungsten (a strategic metal) to Nazi Germany during the conflict; amid heavy diplomatic pressure from the Allies, the supplies decreased after the signing of a secret deal between Spain, the United States and the United Kingdom on 2 May 1944 that led to the fixing of a drastic limit on exports of tungsten to Germany and the ejection of German spies from Spanish soil.[7]

 Sweden – Sweden and the other Nordic countries announced in advance of World War II that they planned to be neutral in any large European conflict. When Finland was invaded by the Soviet Union in the Winter War, Sweden changed its position to that of a non-belligerent, which was not defined by international treaties, thus freeing Sweden of the restrictions of neutrality. Among other things, it allowed the Swedish government to support Finland during the Winter War and allowed German soldiers on leave to travel through Sweden, and a combat division was once allowed to travel from Norway to Finland through Sweden. The later transit of German troops through Finland and Sweden and Swedish iron-ore mining during World War II helped the German war effort. Sweden had disarmed after World War I and was in no position to resist German threats militarily by 1940.

In 1943, the Swedish Armed Forces were much improved, and all such deals with Germany were terminated. Hitler considered invading Sweden, but when Göring protested, Hitler dropped the plan. SKF supplied the majority of ball-bearings used in Germany and were important also to Allied aircraft production.[8]

Swedish Intelligence cracked the Geheimschreiber and shared decrypted information with the Allies. Stalin was informed well in advance about Hitler's planned invasion of the Soviet Union but chose not to believe the information.

Danish resistance worked with Sweden and effected the 1943 rescue of the Danish Jews by shipping the Jews to Sweden. During the Liberation of Finnmark, it sent Norwegian "police" troops over the border to link up with Allied forces. At the end of the war, it was preparing to invade Norway and Denmark with the Allies if the occupying Wehrmacht forces had refused to accept a general armistice.

•   Switzerland – Switzerland maintained its neutrality so as to protect its own banking interests from plunder by the Axis. It also depended on German coal, with 10 million tons imported during the war, making up 41% of Swiss energy supplies. Often, Swiss soldiers opened fire on Axis bombers invading their airspace. On several occasions, Switzerland also shot down Allied planes. Throughout the war, cities in Switzerland were accidentally bombed by both Axis and Allied airplanes. Adolf Hitler did indeed plan to invade Switzerland, but Switzerland had formed complex fortifications and amassed of thousands of soldiers in the mountains to thwart any Axis invasion. Because of the extreme mountainous conditions in Switzerland, Hitler decided to bombard the United Kingdom rather than engage in a costly war with Switzerland.

•  Andorra

•  Liechtenstein

•  Monaco (occupied by Italy and later Germany)

•  San Marino (briefly occupied by Germany, 17–20 September 1944; declared war on Germany, 21 September 1944)

•   Vatican City, see Vatican City in World War II

•  Afghanistan remained neutral throughout World War II.

•  Bhutan remained neutral throughout World War II.

•  Iran was neutral but occupied by the Allies (see Anglo-Soviet invasion of Iran).

•  Saudi Arabia severed diplomatic contacts with Germany on 11 September 1939, and with Japan in October 1941. Although officially neutral, the Saudis provided the Allies with large supplies of oil. Diplomatic relations with the United States were established in 1943. King Abdul Aziz Al-Saud was a personal friend of Franklin D. Roosevelt. The Americans were then allowed to build an air force base near Dhahran.[9] Saudi Arabia declared war on Germany on 28 February 1945 and Japan on 1 April 1945, but no military actions resulted from the declaration.

•  Turkey was neutral until several months before the end of the war, at which point it joined the Allies. Prior to the outbreak of war, Turkey signed a Mutual Aid Pact with France and Britain in 1939. After the German invasion of France, however, Turkey remained neutral, relying on a clause excusing them if military action might bring conflict with the USSR. In June 1941, after neighbouring Bulgaria joined the Axis and allowed Germany to move troops through to invade Yugoslavia and Greece, Turkey signed a treaty of friendship with Germany. Winston Churchill and his military staff met the Turkish president on 30 January 1943 in the Adana Conference, although Turkey did not then change its position.
• Turkey was an important producer of chromite, a strategic material for metallurgy to which Germany had limited access. The Germans wanted it, and the Allies wanted to prevent them getting it, so chromite was the key issue in Turkey's negotiations with both sides. Turkey would backpedal on its agreement to supply Nazi Germany with chromite after instead selling it to the rival nations the United States and the United Kingdom after the two allied nations agreed to also purchase dried fruit and tobacco from Turkey as well.[10] Turkey halted its sales to Germany in April 1944 and broke off relations in August. In February 1945, after the Allies made its invitation to the inaugural meeting of the United Nations (along with the invitations of several other nations) conditional on full belligerency, Turkey declared war on the Axis powers, but no Turkish troops ever saw combat.

•  Yemen remained neutral throughout World War II.

•  Nicaragua Nicaragua declared war on Japan immediately after the attack on Pearl Harbor. Three days later, on 11 December, Nicaragua declared war on Germany and Italy, and, on 19 December, on Bulgaria, Romania, and Hungary. Out of these six Axis countries, only Romania reciprocated, declaring war on Nicaragua on the same day (19 December 1941).

•  United States – The United States remained neutral at the outbreak of World War II in compliance with the Neutrality Act of 1936 despite favoring the Allied side. However, the sudden defeat of France by Nazi Germany in the spring of 1940 led the country to significantly expand its armed forces through the Selective Training and Service Act of 1940. On 29 December of that year, President Franklin D. Roosevelt declared that the United States was to be the "Arsenal of Democracy" for the Allies by giving them supplies while the country remained neutral. The U.S. remained neutral until 8 December 1941, when it declared war on Japan in response to the surprise attack on Pearl Harbor the previous day.