# Why didn't Britain and France declare war on the USSR when it invaded Poland in 1939?

**URL:** <https://boards.straightdope.com/t/why-didnt-britain-and-france-declare-war-on-the-ussr-when-it-invaded-poland-in-1939/156073>\
**Category:** Factual Questions\
**Created:** [February 19, 2003, 4:58am UTC](https://boards.straightdope.com/t/why-didnt-britain-and-france-declare-war-on-the-ussr-when-it-invaded-poland-in-1939/156073 "2003-02-19T04:58:06Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Hermann\_Cheruscan](https://avatars.discourse-cdn.com/v4/letter/h/b782af/32.png) [@Hermann\_Cheruscan](https://boards.straightdope.com/u/Hermann_Cheruscan)\
**Post date:** [February 19, 2003, 4:58am UTC](https://boards.straightdope.com/t/why-didnt-britain-and-france-declare-war-on-the-ussr-when-it-invaded-poland-in-1939/156073/1 "2003-02-19T04:58:06Z")

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I’m not really knowledgeable about that era in history, but I do know that Germany and Russia decided to carve up Poland. When Germany invaded Poland, Britain and France declared war. When Russia invaded Poland days later, there was no declaration of war on Russia from Britain and France. Why is that ?

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**Author:** ![Duckster](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/duckster/32/1244_2.png) [@Duckster](https://boards.straightdope.com/u/Duckster)\
**Post date:** [February 19, 2003, 6:24am UTC](https://boards.straightdope.com/t/why-didnt-britain-and-france-declare-war-on-the-ussr-when-it-invaded-poland-in-1939/156073/2 "2003-02-19T06:24:57Z")

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This might help - [http://www.auburn.edu/~sealyke/wwii/poland.html](http://www.auburn.edu/~sealyke/wwii/poland.html)

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**Author:** ![MEBuckner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mebuckner/32/2896_2.png) [@MEBuckner](https://boards.straightdope.com/u/MEBuckner)\
**Post date:** [February 19, 2003, 6:55am UTC](https://boards.straightdope.com/t/why-didnt-britain-and-france-declare-war-on-the-ussr-when-it-invaded-poland-in-1939/156073/3 "2003-02-19T06:55:23Z")

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We had another thread on this not too long ago, [WW II - Why didn’t the Allies declare war on the USSR?](http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=127155), if you want to see what was said there.