The Phoney War
Following the invasion of Poland in the fall of 1939, World War II lapsed into a lull known as the "Phoney War." During this seven-month interlude, the majority of fighting took place in secondary theaters as both sides sought to avoid a general confrontation on the Western Front and the possibility of World War I-style trench warfare. At sea, the British began a naval blockade of Germany and instituted a convoy system to protect against U-boat attacks. In the South Atlantic, ships of the Royal Navy engaged the German pocket battleship Admiral Graf Spee at the Battle of the River Plate (December 13, 1939), damaging it and forcing its captain to scuttle the ship four days later.
The Value of Norway
A neutral at the beginning of the war, Norway became one of the principal battlefields of the Phoney War. While both sides initially were inclined to honor Norwegian neutrality, Germany began to waver as it depended on shipments of Swedish iron ore that passed through the Norwegian port of Narvik. Realizing this, the British started to see Norway as a hole in the blockade of Germany. Allied operations were also influenced by the outbreak of the Winter War between Finland and the Soviet Union. Seeking a way to aid the Finns, Britain and France sought permission for troops to cross Norway and Sweden en route to Finland. While a neutral in the Winter War, Germany feared that if Allied troops were permitted to pass through Norway and Sweden they would occupy Narvik and the iron ore fields. Unwilling to risk a possible German invasion, both Scandinavian nations denied the Allies request.
In early 1940, both Britain and Germany began to develop plans to occupy Norway. The British sought to mine Norwegian coastal waters to force German merchant shipping out to sea where it could be attacked. They anticipated this would provoke a response from the Germans, at which point British troops would land in Norway. German planners called for a large-scale invasion with six separate landings. After some debate, the Germans also decided to invade Denmark in order to protect the southern flank of the Norway operation.
Commencing almost simultaneously in early April 1940, the British and German operations soon collided. On April 8, the first in a series of naval skirmishes began between the ships of the Royal Navy and the Kriegsmarine. The next day, the German landings began with support provided by paratroopers and the Luftwaffe. Meeting only light resistance, the Germans quickly took their objectives. To the south, German troops crossed the border and quickly subjugated Denmark. As German troops approached Oslo, King Haakon VII and the Norwegian government evacuated north before fleeing to Britain.
Over the next few days, naval engagements continued with the British winning a victory at the First Battle of Narvik. With Norwegian forces in retreat, the British began sending troops to assist in stopping the Germans. Landing in central Norway, the British troops aided in slowing the German advance but were too few to stop it completely and were evacuated back to England in late April and early May. The failure of the campaign led the collapse of British Prime Minister Neville Chamberlain's government and he was replaced with Winston Churchill. To the north, British forces recaptured Narvik on May 28, but due to the events unfolding in the Low Countries and France they withdrew on June 8 after destroying the port facilities.
The Low Countries Fall
Like Norway, the Low Countries (the Netherlands, Belgium, & Luxembourg) desired to stay neutral in the conflict, despite efforts from the British and French to woo them to the Allied cause. Their neutrality ended on the night of May 9/10 when German troops occupied Luxembourg and launched a massive offensive into Belgium and the Netherlands. Overwhelmed, the Dutch were only able to resist for five days, surrendering on May 15. Racing north, British and French troops aided the Belgians in the defense of their country.
The German Advance in Northern France
To the south, the Germans launched a massive armored attack through the Ardennes Forest led by Lieutenant-General Heinz Guderian's XIX Army Corps. Slicing across northern France, the German panzers, aided by tactical bombing from the Luftwaffe, conducted a brilliant blitzkrieg campaign and reached the English Channel on May 20. This assault cut off the British Expeditionary Force (BEF), as well as a large number of French and Belgian troops, from the rest of the Allied forces in France. With the pocket collapsing, the BEF fell back on the port of Dunkirk. After assessing the situation, orders were given to evacuate the BEF back to England. Vice Admiral Bertram Ramsay was tasked with planning the evacuation operation. Beginning on May 26 and lasting nine days, Operation Dynamo rescued 338,226 soldiers (218,226 British and 120,000 French) from Dunkirk utilizing an odd assortment of vessels ranging from large warships to private yachts.
As June began, the situation in France was bleak for the Allies. With the evacuation of the BEF, the French Army and remaining British troops were left to defend a long front from the Channel to Sedan with minimal forces and no reserves. This was compounded by the fact that much of their armor and heavy weapons had been lost during the fighting in May. On June 5, the Germans renewed their offensive and quickly broke through the French lines. Nine days later Paris fell, and the French government fled to Bordeaux. With the French in full retreat south, the British evacuated their remaining 215,000 troops from Cherbourg and St. Malo (Operation Ariel). On June 25, the French surrendered, with the Germans requiring them to sign the documents at Compiègne in the same rail car that Germany had been compelled to sign the armistice ending World War I. German forces occupied much of northern and western France, while an independent, pro-German state (Vichy France) was formed in the southeast under the leadership of Marshal Philippe Pétain.Previous: Causes of WWII in Europe | World War II 101 | Next: The Eastern Front