This was the name given to the evacuation of British, French and Belgian troops from the port of Dunkirk on the coast of Northern France in 1940.

The Phoney War came to an abrupt end in April 1940. Nazi Germany attacked Denmark, Norway, Holland, Belgium and France. As a response to this French troops moved northwest away from the Maginot Line to support the British Expeditionary Force who had been sent to Belgium. This left 160 kilometres of the Maginot Line in the Ardennes on the border between Belgium and France to be protected by a small force. The German army was able to cross this border almost without opposition and then to divide into 2 columns – one moving towards the Channel coast, the other on to capture Paris. The BEF, French and Belgian armies were trapped. Those who could retreated towards the Channel coast of France. Eventually about 300.000 British, French and Belgian soldiers were trapped in a few square kilometres surrounding the small port of Dunkirk.

The soldiers were stranded on the beach fearing the worst, defeat, capture and death. The British realising that the battle was lost made plans codenamed Operation Dynamo to see how many Allied soldiers could be removed to the relative safety of England. Just at this moment, Hitler ordered his troops to stop 10 kilometres outside of Dunkirk after Goering had promised that air power alone could win the battle and that the Luftwaffe would not allow a single soldier to escape. The German commanders could only look on in frustration as boats of all shapes and sizes (about 900) including fishing boats, fire ships, paddle steamers, private yachts, Belgian barges as well as Merchant and Royal Navy vessels evacuated as many soldiers as they could. The evacuation lasted from May 30 to June 4. and went down as one of the greatest rescue missions in history.

Churchill referred to the evacuation at Dunkirk as a "miracle" and to the "Dunkirk spirit" (of triumphing in the face of adversity) This phrase is sometimes still referred to in Great Britain today. The evacuation provided a great boost to British morale at a time of disaster. Despite this Churchill was cautious and said:

"…we must be very careful not to assign to this deliverance the attributes of a victory. Wars are not won by evacuations."