Anglo-Soviet War of 1919

http://en.wikipedia.org/wiki/Kalmyk_Project

I found this and thought it was interesting. The Soviets planned to undermine British imperialism by invading India. They had thought up two invasion routes they could use. One from Afghanistan (allying with some tribes) and another from Tibet.

How would such a war play out?

Badly for the Soviets.

The British Indian Army will be able to deploy much heavier forces to the region than the Red Army.
Bluntly, I would expect the Raj alone to be able to defeat what paltry forces the Soviets could get through Afghanistan or Tibet, without any help from the UK; without a massive effort by the Soviets to pacify Afghanistan and build logistical links, they'll never be more than a nuisance in this theatre; and the Soviet Union ought to have much bigger fish to fry at this point than being a nuisance to the British Raj on the North West Frontier (a region that in fact saw fairly continuous low level conflict throughout this period, IIRC).
 
Russia was just getting done with the civil war at this point so I don't think it would go well for them. That plus the British Indian army was a force to be reckoned with so I don't even think the soviets could have ever taken India from the British before independence.
 
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