Basically what the title says.
Now ignoring for a second how plausible a successful revolution is, what kind of effects can it have?
It could be argued that the revolution was successful IOTL; after-all the events of 1905 directly lead to the creation of the Duma and the multi-party system. So a more successful 1905 Russian Revolution would further that; a parliament that sits continually instead of being called by the Tsar, with some actual power and checks on the emperor, etc. Assuming WWI happens on schedule there's likely no 1917 Revolution, so Russia stays in the war and the German forces IOTL used in the Spring Offensive are stuck on the Eastern Front. Might lead to an earlier end of the war and even harsher terms for the Central Powers![]()
This is assuming the war even happens.
One of the reason the Germans were so eager to start it when they did was because the Russians planned to modernize their military around 1917. The German military expected that 1914 would be their last chance to knock the Russians down before the Russian military would be too modernized to deal with.
If the Russian military is modernized around 1914 then odds are highly likely that the Germans won't be so eager to encourage the Austrians to mess with Serbia. So you could end up butterflying away WW1 if only because the Germans know they can't win in the long run.
Or an earlier war; The Tangier Crisis, Agadir Crisis, or Bosnian Crisis could have spiraled out of control - particularly the latter. Either way though Russia is in many important ways in a stronger position than she was IOTL.
Russia needed at least twenty years of modernisation to catch up to Germany in 1917, I doubt that social revolution will do much to increase the industrial base, Witte failed for just that reason.
That certainly didn't stop them from going to war in 1914 though.
Not at all, but it's likely that a constitutional Russian Duma is more likely to block going into a war any earlier than OTL's 1914.
Citation?
The French, who were republican, and the British, who had a strong parliament, both went to war in 1914 even with independent legislatures.