By mid-1940, Nazi Germany had swept over Western Europe, conquering France and holding territory from the English Channel north to Norway.
Late that summer, Hitler and the German Luftwaffe turned their attention to England, with the Nazi dictator aiming to use his air forces to soften up Great Britain for an eventual ground invasion — codenamed Operation Sea Lion.
In its way stood Prime Minister Winston Churchill and the recently formed RAF Fighter Command, which could field the Hawker Hurricane and the Supermarine Spitfire, some of the best fighter aircraft in the world at the time.
The Battle of Britain raged in the skies above southern England from late June to October 1940. Nazi fighters and bombers raked the English countryside, cities, ports, and airfields with bullets and bombs over this period.
On September 15, the RAF achieved a seminal victory, downing 56 Luftwaffe planes while losing 28.
Two days later, Hitler postponed Sea Lion "until further notice." He kept invasion forces at high readiness, but Sea Lion was finally scrapped in February 1942.
Even with the invasion looking less likely, Nazi Germany continued to launch attacks on England — some of which would claim thousands of lives in and around London in a night — carrying out the Blitz from late 1940 to mid-1941, when Hitler redeployed his air forces to participate in the invasion of Russia.
Field guns are pictured in preparation to defend against possible invasion, with nonstop training in all kinds of warfare going at military centers all over Britain, July 9, 1940. During training, a mimic battle was held during which a creeping barrage was laid down and machine-gun nests and other strong points were attacked.
A dead German pilot lies among the wreckage of his Ju 87 Stuka dive bomber, which was brought down over Sussex during the Battle of Britain, in August 1940.
Skies over England are the broad canvas on which are painted the picture of war. Here, a German raider wheels through bursts of antiaircraft fire above a southeast coastal area in England. At the right, a barrage balloon falls in flames during the same August 11, 1940, attack.
Two German Luftwaffe Ju 87 Stuka dive bombers are seen returning from an attack against the British south coast, during the Battle of Britain, on August 19, 1940.
Wearing a steel helmet, English Prime Minister Winston Churchill is seen in an observation post in Dover, England, August 28, 1940, as he watched an air battle through field glasses. The mayor of Dover is shown at left.
A Nazi Heinkel 111 bomber flies over London during the Battle of Britain in the autumn of 1940 during World War II. The Thames River runs through the center. The Tower Bridge is visible near the plane's left wingtip.
Two German Dornier 217 planes pass over the burning bombing targets of the Breckton Gas Works at Silvertown, a suburb in southeast of London, during the Battle of Britain in autumn 1940.
The condensation trails from German and British fighter planes engaged in an aerial battle in the sky over Kent, along the southeastern coast of England, on September 3, 1940, during World War II.
The tail of a British Hurricane fighter that was in a battle with Nazi planes over the Channel, at an airfield somewhere in England, Sept. 6, 1940. Despite riddled control surfaces, the plane made a safe landing.
A cloud of black smoke rises from a blazing Nazi fighter that crashed and burst into flames after having been shot down in an air battle over Sussex, September 8, 1940.
One of the many German planes that met their doom during the German air raid on Britain, September 8, 1940. The Nazi fighter was photographed as it falls after being shot down in an air battle. It crashed and burst into flames.
Three British boys, who arrived in New York City aboard the Cunard line Samaria on October 3, 1940, refugees from war, hold souvenirs of the battle of Britain, pieces of shrapnel and bullets. Left to right are: Ralph Polar, 12; Roger Simon, 14; and David Dawkings, 14.
A forward machine gunner is seen sitting at his battle position in the nose of a German Heinkel He 111 bomber plane, while en route to England in November 1940.
A British RAF fighter pilot bails out after the wing of his Hawker Hurricane aircraft is torn off by a German fighter plane, in a dogfight over England, in November 1940.
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