USSR intervenes in defense of Poland in 1939

As it says on the tin. Stalin, fearing the German war machine and desiring a buffer state, reverses his decision in late August and decides he will support the territorial integrity of Poland.


Stalin makes this decision and informs his high command, but does not announce it internationally. Like the Molotov-Ribbentrop Pact. When Germany declares war on 1 September, 1939, the Red Army is ordered to cross the Polish border and help the defenders. Naturally, they ask the Polish government first, but they're pretty insistent that they should come. The USSR commits fully to defending Poland and eliminating the Reich at this time. Are they able to fight through the Nazi German troops and end the war early? How does the war develop from here?
 
If Stalin wants a nice quiet buffer state, he's going to demand a whole lot of changes in Polish policy - both foreign policy and policy toward the minorities in eastern Poland - that iOTL Poland categorically refused to make. And, if he demands them before helping the Polish government, they (having no idea of the horror of Nazism or how long it would take Britain and France to defeat Germany) very well might refuse and let themselves be (temporarily, they thought) overrun rather than change their policies.

That said, if Stalin helps Poland anyway... Given the Soviet Army's performance during the Winter War, I wouldn't rely too much on them. But, given how close the Nazi economy was to the knife's edge during the OTL invasion of Poland, and how dependent they were on Soviet raw materials throughout OTL 1940, Germany might collapse anyway.
 
If Stalin wants a nice quiet buffer state, he's going to demand a whole lot of changes in Polish policy - both foreign policy and policy toward the minorities in eastern Poland - that iOTL Poland categorically refused to make. And, if he demands them before helping the Polish government, they (having no idea of the horror of Nazism or how long it would take Britain and France to defeat Germany) very well might refuse and let themselves be (temporarily, they thought) overrun rather than change their policies.

That said, if Stalin helps Poland anyway... Given the Soviet Army's performance during the Winter War, I wouldn't rely too much on them. But, given how close the Nazi economy was to the knife's edge during the OTL invasion of Poland, and how dependent they were on Soviet raw materials throughout OTL 1940, Germany might collapse anyway.
This was pretty much my thought. And dismal performance or no, the USSR has a lot more airplanes than Germany does. Add to that the well-trained Polish air force, and you might have something. Just the volume of manpower will slow Germany down a lot and give Poland more time to get its shit together while giving their transport a reprieve from the constant air attacks. I expect casualties to be horrendous, but who in the USSR gives a shit.

Germany would be so screwed in a long war at this stage. They have no ability to execute Barbarossa this early, and the USSR will be learning from its experience and has far more capability to power through defeats than Germany. Might Romania be persuaded to join the fighting against Germany? A possibility.

Edit: Forgot to mention, but Stalin will probably SAY he doesn't need any policy changes from Poland, but then change his mind when three million men of the Red Army control the entire country. If he does power through and stomp Germany, which I think he can, then Poland will probably become communist whether they like it or not. A la Hungary in '56, or Czechoslovakia in '68.
 
ight Romania be persuaded to join the fighting against Germany? A possibility.
They were allied with Poland before the war (Poland asked them to remain neutral to help with supplies and evacuation), so I'd say it'd be fairly easy if the Soviets are actively fighting on Poland's side.
 
No, the Soviets lack the preparation to burn through Poland and enter Germany, decisively defeating the Heer, right there and then. No way.

They can, however, make a dismal future for Germany (and others, most probably the Poles). They can likely establish a frontline somewhere East of Warsaw, through mutual exhaustion of their own, the German, and the remaining Polish forces. Meanwhile, they are stealing the French's reason not to push with their offensive in the West; that offensive, too, can't go much farther than what the French actually achieved in the first week of September. But the end result is that Germany is bogged down in trench warfare on two fronts - a WWI remake. It's the kind of long war the Allies can support and the Germans cannot.

Also significantly, there is no general realignment in favor of Germany. Romania will probably remain neutral, but won't sell out its precious stuff to Germany. Sweden will also not lower prices. Italy will remain neutral, Hungary ditto. And the Germans won't have the troops and airplanes for Weserübung.

Unfortunately, there isn't much in this for Stalin.
 
Hitler might froth himself to death when he receives the knews of such a betrayal :)

Though this kind of (almost-)altruistic Stalin scenario is borderline ASB, but let's say he has some reasons to behave in this way. Once he has troops on the ground and place at the conference table many things can be gained even if he stays modest in his demands - moving Poland westwards, border corrections here and there, regime changes, influence zones...

TBH replacing much of the little value eastern borderlands with Upper Silesia or East Prussia would be a large gain for Poland, especially if they are permitted to expell the local Germans.


As the Soviets can move quite unopposed they should be somewhat faster than Germans - if they cooperate with Poles they should be able to simply move troops and supplies by train (different track width complicates this, but still) and probably lock the front somewhere in the then central Poland (optimistically the line of Narew-Vistula-San and Warsaw can be held).

Poland stays in the game as a somewhat meaningful player, with remaining bits of industry and still substantial population reserves, if the receive armaments from the allies they should keep thirty divisions or so in the fight.
 
This was pretty much my thought. And dismal performance or no, the USSR has a lot more airplanes than Germany does. Add to that the well-trained Polish air force, and you might have something. Just the volume of manpower will slow Germany down a lot and give Poland more time to get its shit together while giving their transport a reprieve from the constant air attacks. I expect casualties to be horrendous, but who in the USSR gives a shit.
.

Even if Soviets lose a million men in trench warfare meatgrinder (which I think would be unlikely) ,that's a small change compared to the OTL losses, and of course they don't lose industry, infrastructure and so on. Poles would be worse off than the Soviets, as most of the fighting would happen on their territory, but still better than OTL; Germans will have more important things to do than spend effort of purposefully murdering them.

That's assuming they don't simply collapse in short time - Hitler doesn't have a string of victories behind him to force his nation to go to grave with him.
 
I have a different take on this. First if Stalin goes back on his agreement with Hitler I think that dooms him (Hitler) as a leader. The Army arrests him or something but the Nazi government falls. Britain is the one that really has the dilemma at this point. Hitler is gone, and they have a shooting war between Germany and the USSR. Which side do they want to be on? They do NOT want the USSR to take over Poland so at this point I would guess they quickly settle things with the new German government and end that conflict. They would then ask for assistance from Germany to protect Poland from the USSR. It could lead to Britain's underlying goal of toppling the communist government in the USSR. The possibilities are endless here. A very interesting TL.
 
I have a different take on this. First if Stalin goes back on his agreement with Hitler I think that dooms him (Hitler) as a leader. The Army arrests him or something but the Nazi government falls. Britain is the one that really has the dilemma at this point. Hitler is gone, and they have a shooting war between Germany and the USSR. Which side do they want to be on? They do NOT want the USSR to take over Poland...

That's very small change in comparison with making sure the Germans don't tout a submarine fleet and an air fleet. To many, at this time, Hitler was little more than an avatar of the overall Prussian militarism, and replacing him with realistic, hard-eyed generals wouldn't be that big a boon. The British have a war going with Germany, Poland has served as the tripwire and casus belli, and they'll keep at it. The good thing is that without Hitler they may go for a limited-objectives war: as mentioned above, a reduction (again) of the German war-making capability, chiefly, and possibly a release of the earlier small-fish catch (Czechoslovakia). again, not so much because they love the Czechs, but because Germany has to be downsized (again).

The issue, if anything, is whether the German generals do go ahead with that regime-change plan. Not long ago, I would have said it's not impossible. Then thinking again, yes, Hitler being duped in this way should be politically a lame duck. But are we sure the German population at large couldn't be manipulated to be very patriotic (again)?
 
That's very small change in comparison with making sure the Germans don't tout a submarine fleet and an air fleet. To many, at this time, Hitler was little more than an avatar of the overall Prussian militarism, and replacing him with realistic, hard-eyed generals wouldn't be that big a boon. The British have a war going with Germany, Poland has served as the tripwire and casus belli, and they'll keep at it. The good thing is that without Hitler they may go for a limited-objectives war: as mentioned above, a reduction (again) of the German war-making capability, chiefly, and possibly a release of the earlier small-fish catch (Czechoslovakia). again, not so much because they love the Czechs, but because Germany has to be downsized (again).

The issue, if anything, is whether the German generals do go ahead with that regime-change plan. Not long ago, I would have said it's not impossible. Then thinking again, yes, Hitler being duped in this way should be politically a lame duck. But are we sure the German population at large couldn't be manipulated to be very patriotic (again)?

But I would assume that the British know that Germany is nearing financial ruin. The hard pick here is between Germany and Communist Russia. Who do they want getting stronger? Remember no naval battles have happened yet and Germany doesn't really have a big U-boat arm yet. You bring up a good point about the generals and the Army, but many people on both sides had realized the economic damage that the Versailles treaty did to all of Europe. That economic damage leading to political unrest (which had led to Hitler) so I think trying to restore the pre 1914 status quo might seem somewhat attractive to the UK at this point.
 
This was pretty much my thought. And dismal performance or no, the USSR has a lot more airplanes than Germany does. Add to that the well-trained Polish air force, and you might have something. Just the volume of manpower will slow Germany down a lot and give Poland more time to get its shit together while giving their transport a reprieve from the constant air attacks. I expect casualties to be horrendous, but who in the USSR gives a shit.

Germany would be so screwed in a long war at this stage. They have no ability to execute Barbarossa this early, and the USSR will be learning from its experience and has far more capability to power through defeats than Germany. Might Romania be persuaded to join the fighting against Germany? A possibility.

Edit: Forgot to mention, but Stalin will probably SAY he doesn't need any policy changes from Poland, but then change his mind when three million men of the Red Army control the entire country. If he does power through and stomp Germany, which I think he can, then Poland will probably become communist whether they like it or not. A la Hungary in '56, or Czechoslovakia in '68.
Would this also not potentially trigger France and Britain organizing and advancing into Germany from the West?
 
But I would assume that the British know that Germany is nearing financial ruin. The hard pick here is between Germany and Communist Russia. Who do they want getting stronger?

The ones not seeming close to reach hegemony on the Continent.

Remember no naval battles have happened yet and Germany doesn't really have a big U-boat arm yet.

What the British voters would be reading by September 8 would be news of a dozen cargo ships torpedoed or sunk by submarine-laid mines in that week, plus a big headline about the Athenia. 100+ passengers and crew killed on a civilian liner within 48 hours from the Declaration of War.
I do not believe any of that would go down well with: oh, the U-Boot force isn't really big yet. The reaction would be: then let's nip that in the bud now.

You bring up a good point about the generals and the Army, but many people on both sides had realized the economic damage that the Versailles treaty did to all of Europe. That economic damage leading to political unrest (which had led to Hitler) so I think trying to restore the pre 1914 status quo might seem somewhat attractive to the UK at this point.

Save that the British had attempted that already, several times. Including with the London Naval Treaty, with a green light for the Anschluss, with disinterest for the remilitarization of the Rhein, with a favorable mediation in the Sudeten issue, the works. Nothing doing. It was past time for such considerations and measures.
 
The ones not seeming close to reach hegemony on the Continent.

True, but I think the UK feared the expansion of the SU more then a Germany that they just negotiated a end of hostilities with. Just taking what the OP put out there and going on my hunch. IF they got a faverable end to hostilities with Germany I think this is their opportunity to take down the 'Red menace'.

What the British voters would be reading by September 8 would be news of a dozen cargo ships torpedoed or sunk by submarine-laid mines in that week, plus a big headline about the Athenia. 100+ passengers and crew killed on a civilian liner within 48 hours from the Declaration of War.
I do not believe any of that would go down well with: oh, the U-Boot force isn't really big yet. The reaction would be: then let's nip that in the bud now.

This is a good point but the BBC can make this or cover this over (other then the Athena) depending on the changing situation. Hell the Germans might share the magnetic mine technology with the UK as a sign of good faith as part of the negotiations. That in itself would create a lot of goodwill between the governments.

Save that the British had attempted that already, several times. Including with the London Naval Treaty, with a green light for the Anschluss, with disinterest for the remilitarization of the Rhein, with a favorable mediation in the Sudeten issue, the works. Nothing doing. It was past time for such considerations and measures.

Again this would all depend on how they negotiated the end of hostilities. I don't think they would want to break Germany again because they would need the German army against the SU.
 
One advantage of the USSR going to war, the VVS misses the 2nd 1940-41 purge, following up on the '38 Great Purge, of which only 892 Officers of 5616 total were released from Gulag in 1939.

OTL 1941, there was hardly any commissioned officer of the VVS that had more than a few months experience at their current rank. The 1940 Chief of the VVS, Rychagov, had been a Lieutenant in 1937.

That's most pilots, too. During the Winter War, VVS lost 240 in air combat to 62 Finns, and that's not counting the 444 lost in accidents, navigation err and weather.
 
Though this kind of (almost-)altruistic Stalin scenario is borderline ASB, but let's say he has some reasons to behave in this way. Once he has troops on the ground and place at the conference table many things can be gained even if he stays modest in his demands - moving Poland westwards, border corrections here and there, regime changes, influence zones...
It isn't incredibly likely, but I wouldn't call it ASB. This Stalin sees Polish land as a buffer, as OTL, but decides he'd rather have some Poles dying to defend it rather than just Russians.


As others have said, the USSR is going to take massive casualties on the ground and in the air, but they can take it. It almost certainly won't be as bad as the opening of their war actually was, and the fighting will be taking place in Poland more than OTL. The interesting idea is the Western European powers joining the war against the communists. On their own, it would be pissing in the wind, but if the US joins the war it could be a bit problematic for the USSR.
 
A question for those with the knowledge: what is a reasonable expectation for a defensive line the USSR could establish in Poland? How fast could they deploy into the country, what rivers could they shelter behind, and what cities could they expect to reach before the Germans?
 
A question for those with the knowledge: what is a reasonable expectation for a defensive line the USSR could establish in Poland? How fast could they deploy into the country, what rivers could they shelter behind, and what cities could they expect to reach before the Germans?

It's nothing but a ballpark estimate, but I'd say they might be able to stabilize a front from the Lithuanian border to Grodno, to Bialystok, then down to Brest, along a stretch of the Bug to Chelm, then probably a stretch of the San to Przemysl, then to the border.

They couldn't deploy very fast, even assuming this is all pre-planned - they did not have exactly a lot of time since the ink on the Molotov-Ribbentrop pact gets dry. And the OTL advance was disorganized. They would go beyond some of those locations initially, but then the Germans would push them back, before running out of steam themselves.
 
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