The Second World War began on 1 September 1939 when Germany invaded Poland, and Britain and France delcared war as a result. A new type of combined operations tactics which the Germans called Blitzkrieg were used where tanks, troops and aeroplanes attacked together and smashed through any traditional defences. Using this method, Poland was captured in just 28 days, despite heroic, often sucicidal defence of their homeland by the Polish armed forces. After this, the British and French Governments, among others, tried a number of political solutions to prevent the spread of war, all the while reinforcing positions in Northern France with land and air forces from Britain. Known as the Allied Expeditionary Force and Advanced Air Striking Force respectively, these forces moved into position, and waited. This period was know as the 'Sitzkrieg' or 'Phoney War' as the armies stared at one another across the German / French border, and the air forces flew standing patrols and reconnaissance missions, probing for weaknesses. On 9 April 1940, the peace was shattered as the same 'Blitzkrieg' tactics were used against Denmark and Norway. A British Force was sent to help the Norwegians, but the Allied Forces were outnumbered and quickly overwhelmed. Worse was to come.
On 10 May 1940, Germany attacked Belgium, Holland, Luxembourg and France. Twelve fighter squadrons of Royal Air Force were based in France, the only truly modern fighter forces available to the Allies. These Hurricane Squadrons were to support the army, and the Fairey Battle and Bristol Blenheim bomber units which were based in France and operating from Britain. The bomber Squadrons, particularly the Battles, were slaughtered by the German anti-aircraft and fighter units in their attempts to slow the German advance by attacking transport focii, such as bridges. The Hurricanes did their best to protect the bombers and fly their quota of patrols and reconnaissances. However, it was not enough, and when it became clear that the Allies could not stop the Germans, all but three of the Squadrons were called back across the Channel.
The German advance pushed the Allied armies to the sea to a French port called Dunkirk. During what some people called a miracle, 800 small boats managed to lift most of the men off the beaches and back to England. The RAF were successful in keeping the majority of German bombers and fighters away, shooting down 150 aircraft. However, they lost 100 precious fighters and 80 irreplaceable pilots.
By 18 June, all British forces had withdrawn from France. Both the German Air Force (Luftwaffe) and the RAF had lost many aircraft and trained crews during this campaign. Several weeks passed while the Luftwaffe replaced their losses and took over airfields in the countries they had captured. In Britain the time was spent putting as many new fighters and trained pilots into service as possible, to guard against the attack everyone knew was coming. The lull as the German forces consolidated their position was vital to the British armed forces, as it allowed them to prepare. By the beginning of July 1940, the RAF had built up its strength to 640 fighters, but the Luftwaffe had 2600 bombers and fighters. The stage was set. In the skies above South East England, the future of Britain was about to be decided. As the Prime Minister, Winston Churchill put it; "What General Weygrand called the Battle of France is over, the Battle of Britain is about to begin".