Between September, 1939 and March, 1940, almost 400,000 British soldiers went to France. The main body of the British Expeditionary Force moved into North-west France and Belgium. It was to serve as a reserve force in case the Germans broke through the heavily fortified Belgian and French defensive lines. On May 14th German Army Group A made an unexpected breakthrough in the Ardennes Forest on the Belgian-French border. The Allies had considered the forest to be impassible. They were wrong.

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German forces reached the English Channel on May 20th cutting the British and Belgians to the north, from the French to the south. From May 27th until June 3rd over 340,000 British, French and Belgian soldiers were rescued from the beaches of Dunkirk by an improbable "fleet" of small boats, ferries, and ships. The "Miracle of Dunkirk" allowed most of the BEF to escape to Britain - but they left behind virtually all of their equipment.

On June 5th the German army launched an all-out attack on the remaining French defenders. Despite determined French resistance, the Germans captured Paris on June 14th. On June 22nd the French agreed to a cease-fire which in reality was a complete surrender.

On August 13th the German Air Force, the Luftwaffe, began a major air offensive against the Royal Air Force. For over a month German bombers destroyed British airfields, aircraft factories and radar stations in an attempt to destroyed Britain's ability to defend itself. Had this attack been successful the Germans would have then launched a full-scale sea invasion on September 15th, codenamed Operation Sea Lion. By October, 1940, however, the Luftwaffe had suffered such severe aircraft losses that it abandoned daylight bombing attacks completely. Night air raids continued but the British had survived the worst of the German air attacks. The "Battle of Britain" had been won.

The Luftwaffe's failure caused the Germans to postpone their invasion plans - first delaying it to October, 1940, and then into 1941. By May 1941, the threat of an invasion of Britain had ended, and Hitler's attention turned to "Operation Barbarossa", the invasion of the Soviet Union.

Here are three video clips about the battle. The first two are from the 1969 film, "The Battle of Britain", the third is actual film from the air combat.

From "The Battle of Britain in Colour" (1940) 2:48

From "The Battle of Britain: No Escorts"(1969) 5:24

From "The Battle of Britain: The Final Battle" (1969) 5:09