On This Day

Adolf Hitler indefinitely postpones Operation Sealion, the planned German invasion of Great Britain

Operation Sea Lion, also written as Operation Sealion (German: Unternehmen Seelöwe), was Nazi Germany's code name for their planned invasion of the United Kingdom.

Operation Sea Lion, also written as Operation Sealion (German: Unternehmen Seelöwe), was Nazi Germany's code name for their planned invasion of the United Kingdom. It was to have taken place during the Battle of Britain, nine months after the start of the Second World War. Following the armistice with France after the Battle of France, Adolf Hitler, the German Führer and Supreme Commander of the Armed Forces, hoped the British government would accept his offer to end the state of war between the two. He considered invasion to be a last resort, to be used only if all other options had failed.

As a precondition for the invasion of Britain, Hitler demanded both air and naval superiority over the English Channel and the proposed landing sites.

Historical Significance

Operation Sea Lion, also written as Operation Sealion (German: Unternehmen Seelöwe), was Nazi Germany's code name for their planned invasion of the United Kingdom.

Key People

Adolf Hitler

Events Before

  1. Jim Bakker is born

    Jim Bakker televangelist, known for american televangelist, was born on 1939-01-02. James Orsen Bakker is an American televangelist and convicted felon.

  2. American future MLB catcher Roy Campanella (18) weds Bernice Ray; eventually divorce

    American future MLB catcher Roy Campanella (18) weds Bernice Ray; eventually divorce

  3. Adolf Hitler threatens Jews during his speech to the German Reichstag (Parliament)

    Adolf Hitler (20 April 1889 – 30 April 1945) was an Austrian-born German politician who was the dictator of Germany during the Nazi era, which lasted from 1933 until his suicide in 1945.

  4. American singer Frank Sinatra (23) marries 1st wife Nancy Barbato (21) at Our Lady of Sorrows catholic church in Jersey

    American singer Frank Sinatra (23) marries 1st wife Nancy Barbato (21) at Our Lady of Sorrows catholic church in Jersey City, New Jersey; divorce in 1951

  5. Mahatma Gandhi begins a fast in Bombay to protest against autocratic rule in India

    Mahatma Gandhi begins a fast in Bombay to protest against autocratic rule in India

Events After

  1. US President Franklin D. Roosevelt delivers his Four Freedoms speech during his State of the Union address, outlining fr

    US President Franklin D. Roosevelt delivers his Four Freedoms speech during his State of the Union address, outlining freedom of speech and worship and freedom from want and fear [1] [2]

  2. New Fourth Army Incident: Chinese Kuomintang forces under orders from Chiang Kai-shek fire on the surrounded Communist N

    New Fourth Army Incident: Chinese Kuomintang forces under orders from Chiang Kai-shek fire on the surrounded Communist New Fourth Army at Maolin, Anhui Province, killing or capturing about 7,000 troops

  3. Duke Ellington and his Orchestra first record "Take the 'A' Train" written by Billy Strayhorn, at RCA Studio in Hollywoo

    Duke Ellington and his Orchestra first record "Take the 'A' Train" written by Billy Strayhorn, at RCA Studio in Hollywood, California; it goes on to become his signature tune

  4. Future CIA Director William J. Casey (27) weds Sophia Kurz

    Future CIA Director William J. Casey (27) weds Sophia Kurz

  5. American Actress Hattie McDaniel (45) weds real estate salesman James Lloyd Crawford; divorced 1945

    American Actress Hattie McDaniel (45) weds real estate salesman James Lloyd Crawford; divorced 1945

More from the 1940s

Frequently Asked Questions

What happened on September 17, 1940?
Operation Sea Lion, also written as Operation Sealion (German: Unternehmen Seelöwe), was Nazi Germany's code name for their planned invasion of the United Kingdom. It was to have taken place during the Battle of Britain, nine months after the start of the Second World War. Following the armistice with France after the Battle of France, Adolf Hitler, the German Führer and Supreme Commander of the Armed Forces, hoped the British government would accept his offer to end the state of war between the two.
Why is Adolf Hitler indefinitely postpones Operation Sealion, the planned German inv... significant?
Operation Sea Lion, also written as Operation Sealion (German: Unternehmen Seelöwe), was Nazi Germany's code name for their planned invasion of the United Kingdom.
Who was involved in Adolf Hitler indefinitely postpones Operation Sealion, the planned German inv...?
Key figures include Adolf Hitler.

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