I think the recent historiography of the Molotov-Ribbentrop Pact has established that while the USSR was negotiating in bad faith - it had less than friendly intentions toward Poland and the Baltics and intended to convince the UK/France to countenance its schemes in exchange for military cooperation - there was a possibility that its support could be obtained by the UK/France with a bit more diplomatic wrangling. A more favorable response to Molotov on concretely defining "indirect aggression" by Germany against the Baltics and Finland in July (Which France supported) followed by the speedy arrival by plane of their delegations to discuss a military convention (With authority to discuss political topics) could tip the balance. Poland would still refuse to allow Soviet troops on its soil in late August, but productive negotiations on a military convention (Specifying mobilization of all parties in the event of war) could have led the USSR to hold off an signing a concrete agreement with Hitler on the 24th.
If the UK's defense agreement with Poland is delayed by a day until August 26th, Hitler invades at 4:00 AM that morning as he had decided on August 12th. The UK and France issue an ultimatum to Germany to withdraw from Poland on August 29th, and after Hitler rejects this ultimatum the two declare war.
The USSR is caught in a diplomatic mess, having failed to negotiate a concrete agreement with either party and run the clock out with its shenanigans. Under Anglo-French pressure, it begins mobilization on August 28th under MP-22 but refuses to declare war without Polish permission to enter their territory and guarantees that its Baltic interests will be secured. The Poles refuse to accept this stipulation until September 16, with Warsaw surrounded and the Polish armed forces in shambles. Molotov issues a warning to Ambassador Schulenberg on September 10 that the continued presence of German forces on Polish territory of Soviet "national interest" (East of the Curzon Line) would be interpreted as a "hostile act". Hitler rejects the warning as a bluff later that day.
The USSR continues military coordination with France and the UK, and is displeased that the UK has only 6 divisions to immediately deploy to the continent in support of France's 100. After Hitler rejects Molotov's ultimatum, Voroshilov formally inquiries about Anglo-Soviet-French coordination on offensive operations should the USSR enter the war within the next 10 days. The French begin the Saar Offensive on September 12 with probing attacks, with the promise to expand the offensive should the USSR enter the war.
Soviet forces enter Poland at 6:00 AM on September 18. Molotov calls Ambassador Schulenberg to his office to formally issue the Soviet declaration of war at 7:20 AM.
MP-22 calls for the mobilization of 173 rifle divisions, 29 cavalry divisions, 4 mechanized corps, and 40 tank brigades, out of 84 peacetime divisions, 24 cavalry divisions, 4 mechanized corps, and 20 tank brigades. In wartime 29 rifle divisions would be deployed in the Far East, 2 divisions in Central Asia, 29 divisions in the middle of the country (Siberia, Urals, Volga MDs), 16 divisions in the Caucasus, 42 divisions in Ukraine, 8 at the Romanian border, 31 in the "middle direction" (Moscow + Belarus), and 17 in the Leningrad MD.
I believe the RKKA would take a cautious approach and not immediately remove its divisions in Central Asia, the Far East, Caucasus, and bordering Romania/Finland. This leaves it with 73 divisions able to immediately mobilize and cross the border and 29 reserves from the Volga/Urals/Siberia deploying in late September. More units may peel off from other fronts as-needed throughout Autumn.
The Germans will have 66 divisions, 10 of which will be besieging Warsaw and an indeterminate number mopping up various pockets. The German 10th and 14th Armies, 37 divisions, will fight the Ukrainian Front and perhaps 300,000 Poles in various units in Southeastern Poland. 4th and the majority of 3rd Army, 17 divisions, will fight the Belorussian Front. Ukrainian Front has a many good roads leading to Lviv and the Rivne-Lublin road which dictate how the fighting will start, while Belorussian Front is in a much more austere theater with fewer good roads aside from the Minsk-Brest and Minsk-Bialystok routes.
General pros and cons for both sides:
1. Armaments - Soviets lack modern tanks, but German's are pre-modern as well. The Germans got good knockouts with organic infantry AT guns in 1941 anyway, so the likely outcome in my mind is both sides bleed off AFVs rapidly (Germans lost 1/5 of their tanks permanently to the Polish campaign) no matter who wins the initial fight. The USSR is qualitatively behind on aircraft. For munitions, the RKKA has about 900 rounds per/gun, similar to the 1941 campaign. German industry won't really kick off ammunition production until early 1940, so while the RKKA starts off at a disadvantage it has the potential to close the gap if production ramps up similar to OTL (30% increase in munitions production from June-July 1941).
2. Technology - The Red Army is distinctly behind here. Poor optics, heftier radios, and no built-in radios for AFVs. All of these combine to give the German Army a substantial force multiplier, as it possessed in 1941.
3. Tactical Skill - This is the hardest section to evaluate, simply because the contexts are very different from 1941 (Half-mobilized transitory army vs German Army at its peak). Soviet tactical abilities are poor, which will lead to inevitable defeat in their initial engagements. But space to mobilize and no imminent threat of invasion and total destruction will give it a learning curve similar to the Winter War with Finland - initial failure and gradual tactical improvement.
4. The wider context - Germany has just finished fighting Poland, with 1,200-1,400 of its AFVs inactive due to combat or mechanical failure. Stocks of fuel and ammo are also low after the month's fighting, and the supply system is struggling to keep its forces moving. As noted above, Germany can defeat the USSR's initial attacks . But its unlikely it can fully expel it from Poland (Beyond the Neman, Styr, and Seret), much less invade Soviet territory. How events develop from the initial battles of September-October 1939 onward are the most interesting factors.
By October 15 the German Army has defeated the Red Army at Grodno and along the Ternopil-Lviv/Rivne-Lublin highways. The Red Army has been driven back to Eastern/Northeastern Poland to consolidate and reinforce, with the remnants of the Polish Army in the Southeastern portion of the country.
How do things proceed from here? Does the French Saar Offensive continue to build up steam in coordination with Soviet efforts? Is German industry able to deliver the additional munitions needed despite the additional strain? Is the Red Army able to tie up enough German troops to prevent them from shifting 100 divisions West to deliver a decisive blow against France in the spring (Germany has 147 divisions mobilized from 1939-1940)? If it is able to attack in strength, does it deliver a crippling blow as IOTL 1940 or merely a serious attack as in 1914? Here's an interesting question, is Germany able to mobilize an anti-Soviet coalition (Finland, the Baltics, Romania, etc.) to even the Eastern Front material balance?
Much to think about. Germany has the material for a 2-3 year war even with a stalemate, so even in the best case scenario for the Entente 2.0 it won't be a fun war.
If the UK's defense agreement with Poland is delayed by a day until August 26th, Hitler invades at 4:00 AM that morning as he had decided on August 12th. The UK and France issue an ultimatum to Germany to withdraw from Poland on August 29th, and after Hitler rejects this ultimatum the two declare war.
The USSR is caught in a diplomatic mess, having failed to negotiate a concrete agreement with either party and run the clock out with its shenanigans. Under Anglo-French pressure, it begins mobilization on August 28th under MP-22 but refuses to declare war without Polish permission to enter their territory and guarantees that its Baltic interests will be secured. The Poles refuse to accept this stipulation until September 16, with Warsaw surrounded and the Polish armed forces in shambles. Molotov issues a warning to Ambassador Schulenberg on September 10 that the continued presence of German forces on Polish territory of Soviet "national interest" (East of the Curzon Line) would be interpreted as a "hostile act". Hitler rejects the warning as a bluff later that day.
The USSR continues military coordination with France and the UK, and is displeased that the UK has only 6 divisions to immediately deploy to the continent in support of France's 100. After Hitler rejects Molotov's ultimatum, Voroshilov formally inquiries about Anglo-Soviet-French coordination on offensive operations should the USSR enter the war within the next 10 days. The French begin the Saar Offensive on September 12 with probing attacks, with the promise to expand the offensive should the USSR enter the war.
Soviet forces enter Poland at 6:00 AM on September 18. Molotov calls Ambassador Schulenberg to his office to formally issue the Soviet declaration of war at 7:20 AM.
MP-22 calls for the mobilization of 173 rifle divisions, 29 cavalry divisions, 4 mechanized corps, and 40 tank brigades, out of 84 peacetime divisions, 24 cavalry divisions, 4 mechanized corps, and 20 tank brigades. In wartime 29 rifle divisions would be deployed in the Far East, 2 divisions in Central Asia, 29 divisions in the middle of the country (Siberia, Urals, Volga MDs), 16 divisions in the Caucasus, 42 divisions in Ukraine, 8 at the Romanian border, 31 in the "middle direction" (Moscow + Belarus), and 17 in the Leningrad MD.
I believe the RKKA would take a cautious approach and not immediately remove its divisions in Central Asia, the Far East, Caucasus, and bordering Romania/Finland. This leaves it with 73 divisions able to immediately mobilize and cross the border and 29 reserves from the Volga/Urals/Siberia deploying in late September. More units may peel off from other fronts as-needed throughout Autumn.
The Germans will have 66 divisions, 10 of which will be besieging Warsaw and an indeterminate number mopping up various pockets. The German 10th and 14th Armies, 37 divisions, will fight the Ukrainian Front and perhaps 300,000 Poles in various units in Southeastern Poland. 4th and the majority of 3rd Army, 17 divisions, will fight the Belorussian Front. Ukrainian Front has a many good roads leading to Lviv and the Rivne-Lublin road which dictate how the fighting will start, while Belorussian Front is in a much more austere theater with fewer good roads aside from the Minsk-Brest and Minsk-Bialystok routes.
General pros and cons for both sides:
1. Armaments - Soviets lack modern tanks, but German's are pre-modern as well. The Germans got good knockouts with organic infantry AT guns in 1941 anyway, so the likely outcome in my mind is both sides bleed off AFVs rapidly (Germans lost 1/5 of their tanks permanently to the Polish campaign) no matter who wins the initial fight. The USSR is qualitatively behind on aircraft. For munitions, the RKKA has about 900 rounds per/gun, similar to the 1941 campaign. German industry won't really kick off ammunition production until early 1940, so while the RKKA starts off at a disadvantage it has the potential to close the gap if production ramps up similar to OTL (30% increase in munitions production from June-July 1941).
2. Technology - The Red Army is distinctly behind here. Poor optics, heftier radios, and no built-in radios for AFVs. All of these combine to give the German Army a substantial force multiplier, as it possessed in 1941.
3. Tactical Skill - This is the hardest section to evaluate, simply because the contexts are very different from 1941 (Half-mobilized transitory army vs German Army at its peak). Soviet tactical abilities are poor, which will lead to inevitable defeat in their initial engagements. But space to mobilize and no imminent threat of invasion and total destruction will give it a learning curve similar to the Winter War with Finland - initial failure and gradual tactical improvement.
4. The wider context - Germany has just finished fighting Poland, with 1,200-1,400 of its AFVs inactive due to combat or mechanical failure. Stocks of fuel and ammo are also low after the month's fighting, and the supply system is struggling to keep its forces moving. As noted above, Germany can defeat the USSR's initial attacks . But its unlikely it can fully expel it from Poland (Beyond the Neman, Styr, and Seret), much less invade Soviet territory. How events develop from the initial battles of September-October 1939 onward are the most interesting factors.
By October 15 the German Army has defeated the Red Army at Grodno and along the Ternopil-Lviv/Rivne-Lublin highways. The Red Army has been driven back to Eastern/Northeastern Poland to consolidate and reinforce, with the remnants of the Polish Army in the Southeastern portion of the country.
How do things proceed from here? Does the French Saar Offensive continue to build up steam in coordination with Soviet efforts? Is German industry able to deliver the additional munitions needed despite the additional strain? Is the Red Army able to tie up enough German troops to prevent them from shifting 100 divisions West to deliver a decisive blow against France in the spring (Germany has 147 divisions mobilized from 1939-1940)? If it is able to attack in strength, does it deliver a crippling blow as IOTL 1940 or merely a serious attack as in 1914? Here's an interesting question, is Germany able to mobilize an anti-Soviet coalition (Finland, the Baltics, Romania, etc.) to even the Eastern Front material balance?
Much to think about. Germany has the material for a 2-3 year war even with a stalemate, so even in the best case scenario for the Entente 2.0 it won't be a fun war.
