German preparation began well before the eve of war in 1939 with the invasion of Poland. When Hitler came to power in 1933 he was able to build, at first secretly, an army, navy and airforce despite the treaty of Versailles disallowing Germany to maintain a proper army. By this time he had built a very powerful war machine. Despite threats from the west the reoccupation of the Rhineland in 1936, the annexation of Austria, Bohemis-Moravia and Memel in 1938 and 1939 happened without retaliation. The British, after declaring war on Germany on the 1st September 1939 did little to assist Poland who surrendered three weeks later. This helped to convince Hitler he was immune to international reaction. With the temporally secured threat from Russia on hold, Nazi forces in 1940 occupied Denmark and attacked Norwegian ports, securing iron ore imports from Sweden, which were vital for Germany's war effort.
Using overwhelming Blitzkrieg tactics or lightning war' Germany's mission was to quickly defeat and occupy a nation before assistance from the west would arrive. After a period of Phony war' Holland, Belgium and France were defeated in quick succession (operation case yellow) in 1940 where British forces were forced to evacuate France. After these quick defeats with little resistance the Wermarch (German army) was poised to invade England.
In the Battle of Britain, 1940, the Luftwaffe sought to achieve air supremacy in the first major confrontation of the war. Many believe this was the major turning point for Germany. Hitler's order to annihilate the Royal Air Force (RAF) was to prepare the way for Operation Seelowe (Sealion) which consisted of three massive armies invading on the south coast of England. It was at this time Germany began to suffer setbacks. Under the orders of the commander-in-chief of the Luftwaffe, Hermann Goering began in early June the softening-up attacks' on British coastal areas and convoys. By the 13th of August or Eagle Day' the all-out air battle began, yet the Germans failed to destroy vital British air warning and radar systems which were much more advanced than their own. This was the first phase of the battle and although German losses were twice that of Britain Air Chief Marshal Sir Hugh Downing (Commanding-in-Chief, RAF Fighter Command) was facing difficulties as replacement fighter numbers dwindled. It was at this time Germany adopted a new approach and reasoned that by attacking the airfields in the southeast they could force the RAF to expose its remaining strength in its defense, which in the beginning seemed promising yet the plan from the start was a gamble. As Wagener stated with the prospect of achieving complete air superioty in sight, an enemy hardly able to resist any longer was given an invaluable breather'
The 15th September marked the Battle of Britain Day' and the Luftwaffe failed to defeat the RAF, having persistently underestimated the capacities of the British fighter defense. Hitler had pushed the date of Operation Sealion back...