Sweden during World War II (Timeline)

This timeline is about events during World War II of direct significance to Sweden, which remained officially neutral throughout the war. For a larger perspective, see Timeline of World War II.

Timeline

Date	Event	Effects on Sweden, and article links
23 August	Molotov-Ribbentrop pact is signed	The Military balance in the Baltic region is shattered.
1 September	The Second World War begins as operation Fall Weiß is carried out by Nazi Germany, and the Invasion of Poland begins. On 3 September, Great Britain, France, Australia, India, and New Zealand declare war on Germany.
17 September	The Soviet Union invades Poland, and enters a state of co-belligerence with Nazi Germany.
28 September, 5, 10 October	The Soviet Union forces Estonia, Latvia, and Lithuania, to accept Soviet military bases on their soil.
6 October	Poland is conquered.
12 October	The Soviet Union demands that Finland cedes Hanko for the construction of a military base near Helsinki and exchange some Soviet and Finnish territories to protect Leningrad.
30 November	The Winter War begins as the Soviet Union tries to invade Finland.
6 December	Swedish Navy lay minefields in international water in Sea of Åland to prevent Soviet submarines from entering the Gulf of Bothnia between Sweden and Finland.	First Swedish support of Finland. Important for further help shipments.
25 December	Sweden declares itself Non-belligerent in the Winter War	Sweden refuses to intervene militarily in the war, but provides economic and material aid, alongside some 8,000 volunteers to the The defense of Finland.
Date	Event	Effects on Sweden, and article links
1 February	To counter the effects of Soviet reinforcements starting to arrive at the war front, Finland asks Sweden to contribute to the war effort with 2 divisions, 20.000 soldiers. Sweden declines, but is willing to raise the roof of the numbers of Swedish volunteers to Finland. Finland explores the option of large scale western intervention in the war.	February crisis of 1940 - The Western Allies offer to send an expeditionary force to Finland, on the condition that it is transited through Norway and Sweden. See Potential allied invasion.
12 March	The Winter War ends in the Moscow peace treaty, and Finland cedes large territories to the Soviet Union
5 April	Great Britain notifies Norway and Sweden of its intentions to place mines on Norwegian territorial waters.
9 April	Nazi Germany carries out Operation Weserübung, and invades Denmark and Norway.	Through the Occupation of Denmark and Norway, Sweden and Finland become totally encircled by the Nazi–Soviet Pact[1] The only window to the outside world is the Finnish harbour of Petsamo. In a note to Sweden, Germany demands: Strict neutrality, no mobilisation, rights to the Swedish telephone lines, continued ore trade, and no Swedish naval activity outside Swedish territorial waters. Sweden intercepts, and tries to decipher, the German teleprinter communications.
12 April	Swedish Foreign minister Christian Günther informs the foreign policy council, that the government has denied Norwegian King Haakon, the Crown Prince, and members of the Norwegian government entrance to Sweden. According to international treaties, Governments in exile are not allowed to exercise their legal powers from a neutral nation.	Relations with Norway worsen.
12 to 16 April	British troops intervene in Norway.
End of April 30	Germany requests transit of weapons and ammunition through Sweden to the troops in Norway.	In accordance to its neutrality, Sweden declines weapon transit as long as Norway is a theatre of war, and names the closeness to the Norwegian brethren as the reason. In reality, except for Petsamo, a free Norway is the last possible way for Sweden to keep a direct contact with nations other than Nazi Germany, and the de facto Soviet-occupied Baltic states, which undoubtedly influenced the decision.
10 May	The German opening of the Western front begins: The invasion of Luxembourg, Belgium, the Netherlands, and France begins.
15 May	The Netherlands surrender to Germany.
17 May	Sweden denies Germany a specified request to transit 3 trains bound for Narvik, consisting of 30 to 40 sealed railroad wagons containing armaments and supplies.	This worsens relations with Germany, and brings Sweden closer to a potential war. As above: Except for Petsamo, a free Norway is the last possible way for Sweden to keep a direct contact with nations other than Nazi Germany, and the de facto Soviet-occupied Baltic states, which undoubtedly influences the Swedish decision. See Weapon transit.
23 May	In Germany, Joachim von Ribbentrop succeeds Hermann Göring as Swedenreferent.	Ribbentrop is deemed as more hostile towards Sweden than his predecessor.
28 May	Belgium surrenders to Germany.
	The Norwegian harbour-city Narvik, of great strategic importance to Germany, falls into Allied hands.	In an attempt to avoid a German ultimatum, and to make direct contact with western nations possible, the Swedish government tries to activate the far fetched Narvik-plan.
2 June	The last of the British troops leave Norway .	The Narvik-plan is deemed irrelevant.
10 June	Norway surrenders to Germany, King Haakon flees to the mountains and is eventually evacuated to Britain.	The northern Finnish harbour of Petsamo becomes Sweden's and Finland's last window to the western world.
	Italy declares war on France and the United Kingdom, and enters a state of co-belligerence with Nazi Germany.
18 June	Sweden agrees to transit German troops on leave, to and from Norway. The Permittenttrafiken (transit of German troops) commences.	Since Norway has surrendered, it is no longer a theatre of war, and the prior Swedish arguments against transit are no longer valid. Although Sweden agrees to allow transit, the details of the agreement are to be drawn up at a later time.
	The Soviet Union occupies the Baltic states of Estonia, Latvia and Lithuania. On July 21 they request membership in the Soviet Union, which is granted in the beginning of August, and the borders of the Soviet Union are moved to the shores of the Baltic Sea.
20 June	Great Britain seizes four Swedish destroyers off the coast of the Faroe Islands. The destroyers are recently bought from Italy and are bound for Sweden. They are only manned by transport-crews.
25 June	France surrenders to Germany.
Sometime in the summer 4 July	Mathematician Arne Beurling deciphers and reverse-engineers an early version of the Siemens and Halske T52.	Sweden is now able to decipher the intercepted German telecommunications.
8 July	The official agreements on the Permittenttrafiken between Germany and Sweden are signed. Transit movements will comprise: 1 daily train (500 men) back and forth Trelleborg–Kornsjö; 1 weekly train (500 men) back and forth Trelleborg–Narvik. The agreement with Germany would later be increased.
15 July	Protests from Norway's exile Cabinet, and from the United Kingdom's government, against Swedish concessions to German demands.
10 July	The Battle of Britain begins.
18 August	An agreement between Germany and Finland states that: The Wehrmacht is granted rights to use the ports of Vaasa, Oulu, Kemi and Tornio; rail lines from the ports to Ylitornio and Rovaniemi; roads from Ylitornio and Rovaniemi to Northern Norway, and to establish depots along the roads.	German troop transfers through Finland
6 September	A troop transfer treaty between Finland and the Soviet Union is signed: The Soviet Union can use rail lines from the Soviet border to Hanko. Only three trains are allowed to be simultaneously in Finland.
7 September	The London Blitz begins.
27 September	The Tripartite Pact is signed in Berlin by Germany, Italy, and Japan, promising mutual aid. An informal name, "Axis", emerges.
28 September	Vidkun Quisling becomes head of state in Norway.
7 October	Germany invades Romania.
30 October	U.S President Franklin D. Roosevelt, during the presidential election campaign, promises not to send "our boys" to war. On November 4, he wins a third term.
Date	Event	Effects on Sweden, and article links
8 February	Jacob Wallenberg delivers intelligence to the Swedish foreign minister Christian Günther, concerning an impending German attack on the Soviet Union. The attack is expected to take place in the last days of May.	A war between Germany and the Soviet Union is seen as to ease Sweden's two biggest problems: The German pressure on Sweden, and the Soviet pressure on Finland.
	US House of Representatives passes the Lend-Lease bill.
4 March	British commandos carry out attack on oil facilities at Narvik in Norway through Sweden	This triggers the March crisis.
27 April	The German battleship Bismarck is sunk in the North Atlantic.
9 May	Finland initiates mobilisation.
22 June	Germany invades the Soviet Union in Operation Barbarossa. Germany demands that Sweden allows transit of Division Engelbrecht from the Norwegian capital Oslo, via Haparanda in Sweden, to the theatre of war in Finland; provide Swedish tonnage for German-Finnish purposes; allow German use of Swedish airspace; etcetera.	Since adherence to these demands will compromise Swedish neutrality, it triggers the Midsummer crisis in Sweden.
25 June	The Continuation war, between the Soviet Union and Finland, starts.	Sweden aids Finland throughout the Continuation war. Internally in the Swedish government this is justified as an effort to keep Finland independent, and thereby in accordance of Swedish neutrality. It is unclear if this was legal.
12 July	Assistance pact signed between the United Kingdom and the Soviet Union.
Fall of 1941 Date needed	Sweden starts trading directly with the German Wehrmacht in Finland. Among other things tents with stoves, and trucks, in exchange for nickel from Petsamo.	This is kept secret from the Western Allies, and most likely a breach of Swedish neutrality..
30 October	Franklin Delano Roosevelt approves US$1 billion in Lend-Lease aid to the Soviet Union.
6 December	The United Kingdom declares war on Finland.
7 December (December 8, Asian time zones)	Japan attacks US forces at Pearl Harbor. The United States and the United Kingdom declare war on Japan.
11 December	Germany and Italy declare war on the United States. The United States reciprocates by declaring war on Germany and Italy
27 December	British Commandos raid the Norwegian port of Vaagso, causing Hitler to reinforce the garrison and defences
Date	Event	Effects on Sweden, and article links
February Date needed	Intense rumors of German offensive operations against Sweden.	The February crisis of 1942 - In Sweden it is believed that Germany regards a preemptive occupation of Sweden as necessary, to prevent Sweden from cooperating with an Allied landing in Norway. The Swedish response is mobilisation.
February Date needed	Germany is treaty-bound to provide Finland with cereal, but several shipments have become frozen into the Baltic ice. Finland requests Sweden to provide cereal to prevent famine.	The treaties concerning safe passage by sea (lejdbåtstrafik) state that Sweden is not legally permitted to deliver cereal to Germany or her allies. The solution is to deliver the cereal to occupied Denmark, and let Germany redistribute it to Finland. This action might be considered questionable, although it technically legal.
Date	Event	Effects on Sweden, and article links
5 August	Sweden notifies Germany that the transit agreement will be cancelled on 15 August.
15 August	The transit agreement is cancelled.	The permittent-trafik stops.
Date	Event	Effects on Sweden, and article links
Spring Date needed	The Finnish government rejects Soviet offers of peace as the Finnish army stands undefeated in the remote Karelia. Sweden advises Finland to make peace with the Soviet Union.	It was unclear what the German response to the Swedish advice would be. All available military units were ordered to fortify the Swedish capital, Stockholm, to heighten the coup defence.
June Date needed	The Finnish President Risto Ryti makes a personal deal with Germany, to refrain from making a separate peace with the Soviet Union, in exchange for continued German shipments of supplies.	Ryti is criticised for this deal by the parliament, and it is unclear whether Finland is still bound to the deal, should Ryti resign.
9 June	A major Soviet offensive commences in the Karelian isthmus.
23 June	The Soviet Union demands Finland to capitulate.
Mid July Date needed	The strongest Soviet units leave Finland to take part in the race to Berlin.
31 July	Ryti submits his resignation.
4 August	Carl Gustaf Emil Mannerheim is sworn in as president of Finland.
19 September	A cease fire between the Soviet Union and Finland is agreed. A clause states that Finland is to disarm and expel the remaining German forces from its soil.	This cease fire makes it clear that Sweden will not share a border with the Soviet Union.
Date	Event	Effects on Sweden, and article links
7 May	Surrender of German forces in Europe

Sources

Notes

1. Fischer, Benjamin B 1999-2000

References

Fischer, Benjamin B (Winter 1999–2000). "The Katyn Controversy: Stalin's Killing Field". CSI Publications. Retrieved 10 December 2005. Isadora Donahue helped in this programing