Britain and France declared war on Germany in September 1939 in response to the invasion of Poland. The period between September 1939 and April 1940 is often called the 'Phoney War' because, although war raged at sea, very little happened in Western Europe during this time.

This changed in April 1940 with British and German actions in Norway. The following month, Germany launched its offensive against the Low Countries and France. It took just six weeks for them to overwhelm the Allied defence. 


5 Facts About the Battle of France

Discover more about the Battle of France and a few highlights from our collection. 


1. Germany used Blitzkrieg techniques

Germany launched air and ground attacks against Belgium and Holland on 10 May. They utilised the same Blitzkrieg methods that had been so effective in Poland, combining tanks, infantry and artillery to overwhelm defences. 


2. Germany attacked through the Ardennes

France, like Britain, anticipated fighting a defensive war similar to the First World War. They placed great faith in the strength of the Maginot Line to defend the French border with Germany. 

With British and French troops rushing into Belgium to meet the German attack, German forces invaded France through the dense forests of the Ardennes. This move bypassed the Maginot Line and outflanked the Allies fighting in Belgium. A two-day battle at Sedan ended in defeat for the French defenders.


3. Allied forces were surrounded at Dunkirk

German forces advanced swiftly to the coast. The Allies, including the bulk of the British Expeditionary Force, retreated to Dunkirk. Rather than counterattack, the decision was made to organise an evacuation from Dunkirk.


4. Paris was declared an open city

German troops entered Paris on 14 June. French forces withdrew from the city the day before and it was declared an ‘open city’ - meaning it would not be defended - in order to prevent its destruction. 


5. The armistice was signed on 22 June

France requested an armistice on 17 June. The document was signed on 22 June in the same railcar where German representatives signed the armistice at the end of the First World War. The car was relocated to the same location in the Compiegne forest.

Listen to an Interview

Ian Roger English was serving in France as an officer in the Durham Light Infantry in May 1940. In this interview, recorded by IWM in 1982, he recalls in detail his experiences of the German invasion and the Allied withdrawal into Dunkirk. 

Listen to the full interview

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