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As many know the Russians had a stiffy for the straights for a very long time. We know that Russia never did take and hold Constantinople and incorporate it into the Empire, much to the British delight. The Russians also had many chances to enter the city.

Twice the Russians could have taken the city without a huge amount of loss. Russo-Turkish War of 1877–1878 and the Russo–Turkish War of 1828–1829 are the two best examples of times when Russia could have taken Constantinople. Lets Say for some reason the British turn a blind eye to it
(yes, I know its near ASB but just humor me). In the Peace Treaty could the Russians have taken the city? Could they have taken the straight?

And another, if the Russians did take it how would the region go on? Would they send colonists to the area, would they repopulate it with Greeks and Russians? Would they form a quasi-Byzantine state or a Greater Hellenic Empire? Could the Ottomans retake the city in another war? Would they even try?
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