High Quality Content by WIKIPEDIA articles! Adlertag ("Eagle Day") was the first day of Unternehmen Adlerangriff ("Operation Eagle Attack"), which was the codename of a German military operation by the Luftwaffe (German Air Force) to destroy the British Royal Air Force (RAF). By June 1940, the Allies had been defeated in Western Europe and Scandinavia. Rather than come to terms with Germany, Britain rejected all overtures for a negotiated peace.