The German Luftwaffe considered August 13, 1940 the beginning of the Battle of Britain. It was called “Aldertag” or “Eagle Day,” and was marked by a series of concentrated air attacks launched against Essex, Kent, Sussex and Hampshire, England. German aviation forces carried out a total of more than 1400 missions and RAF Fighter Command flew more than 720 combat sorties in response.
The strategy behind the German attack was to test the British defenses to gauge whether or not the RAF would be able to successfully divide its defensive force to meet widely disparate attacking forces. It was a day of mixed results for the Luftwaffe. Several high profile targets were completely missed while others, suffered only minimal damage. Within RAF Fighter Command the attacks signaled the beginning of some difficult days, where fighter resources needed to be efficiently deployed in order to meet the greater numbers of German bombers and fighter aircraft.