History London

Operation Sea Lion: Hitler's Failed Invasion of Britain

Nazi Germany had a detailed plan to invade Britain, and it came terrifyingly close to being set in motion.

1 min readKing Charles Street

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We just heard the story about the Cabinet War Rooms, and now we want to tell you more about one of the most fascinating operations of that entire era: Operation Sea Lion, Adolf Hitler's plan to invade Britain by sea.

The idea was straightforward in theory. Germany would first destroy Britain's Royal Air Force, the RAF, leaving the country defenseless from the air. Then, German troops would cross the English Channel and storm the British coastline. The invasion was penciled in for mid-September 1940.

What Hitler hadn't counted on was the RAF's extraordinary resilience. Despite being heavily outnumbered, British pilots, flying aircraft like the Spitfire and the Hurricane, fought back ferociously. A secret weapon gave them a crucial edge: the Chain Home radar system, a network of coastal stations that detected incoming German aircraft early enough to scramble fighters in time.

By late August, Germany's air force, the Luftwaffe, had failed to crack British air defenses. On September 17, 1940, Hitler postponed the invasion indefinitely. It was the first significant military defeat of his war.

Operation Sea Lion never sailed. And somewhere, a very relieved Channel fisherman probably never even knew how lucky he was.

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Sources. Story: historyextra.com Photos: Federal Archives, Image 101II-MN-1369-10A / CC-BY-SA 3.0, CC BY-SA 3.0 DE <https://creativecommons.org/licenses/by-sa/3.0/de/deed.en>, via Wikimedia Commons

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