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PoD # 1

What if the Czechs and Poles occupied all of Silesia, East Prussia and maybe Pomerania during the Ruhr occupation. They justify this publicly by citing their alliances with France.

Their objectives - At a minimum, revision of the postwar treaties so that Germany is committed to demilitarization east of the Oder-Neisse on the model of the Rhineland and inclusion of great power guarantees of their existing borders with Germany.

Militarily, I don't know how they would do, but they have the advantage of the French sitting on the Ruhr on top of the Germans.

I imagine the reactions in the U.S., Britain and Soviet Union will be sharply negative, but positive in France, with those eastern countries forming tighter bonds with France. Disinterested countries will have a a little bit of "WTF?" with the Poles and Czechs, but the French will be glad to have allies.

Can the Poles and Czechs physically do this occupation of far eastern Germany?

Can or will the Germans oppose Polish and Czech actions with any more resistance than they gave to France in the Ruhr (non-violent with some strikes and crowd actions but nothing military)?

If the Germans do as OTL in the west but fight hard in the east, how do the French react?

What is this going to do to German internal politics for the rest of the 1920s and with international diplomacy of the decade like the Locarno Pact, Dawes Plan and Kellog-Briand Pact?

The Soviet Union will be pissed and may have a temptation to retaliate against Poland to secure lands east of the Curzon line, but I tend to think they would be too tired and focused on reconstruction and too fearful of provoking French hostility.

As for Italy, I don't know what Mussolini would do. Was Italy a recipient of any reparations payments from Germany at this time? Were the Germans paying up? I imagine that Italy would seek to manipulate the situation to its advantage and try to gain concessions from one or both sides.

Britain would be angry at all parties, but would they be so mad that they'd be explicit about having no continental commitments for the next two decades? On the other hand, do the British, wanting the conflict to go away, judge they need to appease the Poles and Czechs in some way?

I think that within Germany this dual occupation would boost extremist politics and be bad for the economy. At the same time, the Reichswehr and most German rightists might commit even more deeply to cultivation of the USSR as a German ally.

Could the Germans somehow pull off a surprise, dignity-reviving short-term "win" from such a Ruhr crisis gone pan-European?

PoD #2

If we need to schedule this for a point where the Poles and Czechs would have more motivation, perhaps they could launch their attack during the Locarno Pact negotiations in 1925 as it becomes clear the pact is leaving the permanence of Germany's eastern borders unaddressed, even while guaranteeing the western status quo.

This is militarily riskier, but the eastern powers have more motive to show they cannot be discounted at this point. The biggest change is that France rather than sitting on the Ruhr is pulling back a bit on the Rhineland. The Soviets might feel a little bit more recovered and tempted to intervene, but I doubt it.

I imagine the British here will be pissed at the pissant eastern powers, but might judge there needs to be diplomatic concessions to the Poles and Czechs to quiet things down. The French probably will not be angry at the Poles and Czechs and will become more interested in these countries as allies unless their performance is militarily incompetent.
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