Why Didn't the Allies Declare War on the USSR when it Invaded Poland? (Short Animated Documentary)

As you'll know World War 2 (in Europe) began with Britain and France declaring war on Germany after it invaded Poland. But when the USSR invaded soon afterwards, the allies did nothing. But why? Why was there no declaration of war on the Soviet Union? Find out in this short and simple animated history documentary.

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Sources:
British Reactions to the Soviet Occupation of Eastern Poland in September 1939 by Keith Sword

POLAND IN BRITISH AND FRENCH POLICY IN 1939: DETERMINATION TO FIGHT—OR AVOID WAR? by ANNA M. CIENCIALA

Choosing Not to Choose in 1939: Poland's Assessment of the Nazi-Soviet Pact by MAREK KORNAT

[redandinata]

The blue color in Poland's flag stands for loyal allies

[Grymbaldknight]

*France:* "Should we stop the Soviets invading Poland?"
*UK:* "Nah, maybe leave it. Something tells me that this cooperation between Germany and the Soviets won't last."
_[Germany and the Soviets start fighting]_
*UK:* "See, France, what did i te--- oh, you've been conquered."

[Czar_Moss]

I love how Europe does either A) full continental war that kills millions or B) write a strongly worded letter asking someone to stop committing atrocities

[AloisAgos]

Poland: "Will you be by our side?"
Europe: "We will attend your funeral yes."
Poland: -_-

[Randomperson-tsbm]

When you didn't ask this before but you realise that it is a good question.

[utkb]

UK's Strongly worded letter:

*Dearest Joseph*

*The wasn't very nice of you*
*Best wishes, *
*Neville*

[majike]

"Also, they would've lost."
Sneaking that in there at the last possible second of the video lol

[danielblumberg]

The answer for this question is simple:

They didn’t want USSR to declare war on them as Nazi germany was strong enough alone

[erikthomsen]

France and Britain: “Some of you may die. But that’s a sacrifice I’m willing to make.”

[Czar_Moss]

I love how blissfully naive post ww1 Europe seemed

"we gave Poland independence, so there's no way foreign forces would invade! war problem = solved"

[blackrider]

I love the funnyparts you add to the videos. “…harshest measures known : a strongly, worded letter“. I laughed out loud every single time you drop one of these nuggets into your videos!

[JPGRRocksProductions]

“This is like the fourth time.” As a Pole myself, this cracks me up.

[Robbstark]

Allies: “we aren’t going to start a war with soviets even if it is justified because they’re insanely powerful and we are already engaged on other fronts.”
Axis: “so anyways I started blasting”

[tim_mothy]

I love your videos! So concise and informative, and the animations are so cute!

[waughy]

This guy is the king of answering questions no one thought about

[billt]

I talked to a Brit way long time ago, like in the early 1990's. He said, growing up in school, kids are taught the primary goal of England's foreign policy is "don't ever let anyone unify the continent." Meaning, if any continental power becomes strong, side with their weaker opponents. When Spain was strong, Britain supported Spain's opponents. When Napoleon popped up, Britain supported France's opponents. When Germany got strong, you have to support Germany's opponents, which happened to include the USSR. "The enemy of my enemy is my friend, for now" - perfectly applied.

[deplorabledegenerate]

Also, they were actually drawing up plans to bomb the Caucus oil fields after the USSR's poor performance against Finland. Though, as you might know, the USSR's poor performance against Finland was noticed by someone else who acted first.

[leonw]

I have been asking myself that for a while now, thank you for clearing thinks up.

[ToLWaM]

I’m currently reading the Rise and Fall of the Third Reich. This was actually one of the biggest questions I had going into the book. Basically, the last thing the allies wanted was to be at war with anyone other than Germany.

[riptidemonzarc]

"They both felt that Poland was entirely lost"

... that's funny, because Poland's national anthem is entitled 'Poland is Not Yet Lost"