OK, here's my take, mostly from my EDC notes.
1. In 1890 things start diverging.
2. The Great War (aka The Summer War) starts a month earlier and fizzles out in 1915 after the CPs
[1] (well Germany) go defensive against France (and a less effective UK) and annihilate the Russians.
3. The war ends with Belgium and Luxembourg as German satellites. Russia falls apart
[2] and loses Finland, Poland, the Baltics (and later Ukrania) as nominally independent German satellites.
4. There's a fair bit of post-war unrest in France and the UK
[3]. Ireland becomes independent under a Redmondite federal system
[4] and there is no Easter Rising, War of Independence and Civil War
[5]; there is what might politely be called 'intervention' by Germany
[6].
5. America dozes.
6. Russia manages a multi-sided Civil War (Imperialists, Royalists, Social Democrats, Revolutionaries et cetera) for a few years. Eventually a fairly weak central government emerges, accepts the treaties imposed by Germany (the fait accompli independence of chunks of what had been Greater Russia) and sets about governing. Some warlords survive
[7].
7. So in 1925:
- Germany is pretty quite, digesting the gains and governed by the Social Democrats with a much weakened Kaiser (W-II having died in the war)
- France is no longer chaotic, also governed by Social Democrats and rather pissed at the UK. Rapprochement with Germany is actually becoming a popular idea.
- Ireland is stable and playing Germany, the UK and the US off each other to pay for industrialisation. A youngish chap named Collins is making a bit of a name for himself as is an accountant named Ludgate...
- Britain calmer than it was but the army is still doing a lot of "aid to the civil power" much of which involves shooting people. Scotland is a troublespot and the Labour party is looking like a serious force.
- The US is still a secondary power and busy with trade and commerce. They're rather annoyed at the UK about certain financial matters pertaining to the war.
- Russia is no longer experiencing a civil war and looking like it might emerge as a Great Power again in a decade or two. Germany has noticed this and there is much déjà vu.
- Overall feeling about the war is split between "That was a near thing" and "One more Big Push and we could have finished them"
8. Then it all falls apart. in 1931 the global economy tanks; the Big Slump, the Okie 'flu and the rest of the upheaval of the 1930s.
Russia is badly effected, and the Social Democrat government screws up and is coup'd by a grand coalition of extremists that unified around a programme they could all live with: a windy mix of nationalism, corporatism, anti-liberalism, anti-socialism, social conservatism and reactionary Orthodox Christianity with generous helpings of militarism, anti-Semitism, xenophobia and the Manifest Destiny of the Slavic Peoples to rule Eurasia.... After consolidating power they also began a rather brutal but undeniably effective programme of forced draught industrialisation and military expansion.
9. The rest of the world also developed numerous new political movements in response to the social, political and economic crises.
- There were fascist rumblings in France, quashed by the Socialist government who was increasingly cordial towards Germany.
- Italy and Spain both saw civil wars between Fascist and Communist groups; in the former the country was split into two and not re-unified for decades while Franco-German intervention in Spain eliminated the fascist threat there (and not coincidentally much of the more extreme left-wing also)
- In Ireland the Greenshirt movement's attempt at a popular revolution were stymied by a lack of support and the determination of the Collins government to maintain the peace. Many of the troublemakers were "encouraged" to go to Spain to fight for the Nationalists (though not all of them arrived...) or ended up Britain during the Troubles there.
- The USA effectively becomes deadlocked after the mid-term elections in 1934 and falls apart after the 1936 mess
- In Britain the unresolved post-war unrest reemerges, in Scotland 'Red Clyde' doesn't just refer to the politics. There is a low-level civil war for a few years ('The Troubles') which ends with the coup and the formation of the British Republic (the Ed7/Geo6 business).
10. Then in 1940 the Eastern War (The Autumn War) begins. Bad Things happen.
[1] Also including Sweden and Italy as well as The Usual Suspects
[2] Look at the unrest before the war, The Revolution Was Coming.
[3] Also very much historical but worsened by various factors.
[4] It's complicated
[5] Not actually relevant to Russia as yet.
[6]. "Us? Meddling? Never!" Any thoughts involving Atlantic naval bases, submarines and 'Great War II - This Time We'll Finish the Job' are rampant speculation and utterly unfounded.
[7] Including a certain Mad Baron. I have plans for him...