If the Entente so much as look like they will attempt a rescue operation, the Tsar and his family will bite the dust. The Bolsheviks will not risk letting him become a figurehead for opposition to their regime.
However, there is another way to have the family rescued which is overlooked, is to have the
Germans do it.
Looking at feasibility, it is much easier for the Germans to pull it off. Of course, it also seems counter-productive to rescue a man who's country you were just at war with, but take a look at some of these quotes from
George, Nicholas and Wilhelm: Three Royal Cousins and the Road to World War I
In Moscow, Nicholas’s old court chancellor, Benckendorff, brother of the former British ambassador, tried to get the German ambassador, Mirbach, to support a rescue mission. In Kiev, now occupied by the Germans, Mossolov attempted to persuade the German commanders to back a plan to travel up the Volga to Ekaterinburg. He wrote personally to the kaiser about it. He never received a reply. A former German ambassador to Petrograd told him with much embarrassment that the kaiser couldn’t reply without consulting his government, and the local German commanders refused to help.
The two cousins were also pretty close to eachother, even though their nations were enemies. The Bolsheviks would definitely be opposed to sending over the Tsar, but they would really have no choice.
The Germans could either
a) send a division or two up the Volga river to Yekaterinburg, take the Tsar, and return back to German lines. (not that likely) what is likely however, is
b) the Germans could easily just use threats to make the Bolsheviks hand over the Tsar. Operation Faustschlag had made it obvious that the Red army was in no condition to face the German army, and the Brest-Litovsk had left German troops only a few miles away from Leningrad, and about 320mi from Moscow (not a large distance considering how quickly the Germans took Ukraine). Taking both of these, which was feasible, would probably result in collapse for the Bolsheviks, so they would almost certainly agree to hand over the Tsar.
There were actually rumors that the treaty of Brest-Litovsk inculded a demand for the Russian royal family to be given to the Germans unharmed, iirc.
Anyway, if the Tsar was handed over to the Germans, it would probably be met somewhat bitterly by Nicholas and his family (they would be being taken captive by their enemy) but most likely with some relief as well. They would probably spend the rest of the war in some German palace, and I could see the Kaiser and some of the other princes developing plans to invade Soviet Russia and reinstall Nicholas as a pro-German monarch before the Germans lose. After the war finishes the I would think that the Tsar and his family would move the Britain, France, Denmark, or possibly the Netherlands with the Kaiser. (they were pretty close)(did I already mention that?


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