The spring of 1941 was one of the most successful war periods for the Luftwaffe . German bombers crushed British cities with night raids and delivered hard blows to Royal Navy vessels in the Mediterranean. Luftflotte 4 aircraft effectively supported the lightning victory of the Wehrmacht in Yugoslavia and Greece. German fighters triumphed in air battles over Malta and vigorously entered the North African battlefield. A single minor tone was lost in the symphony of success: the embarrassing result of a special Luftwaffe action to help Iraq's anti-British insurgents.