As we all know, the naval ambitions of Tsar Peter I 'the Proud' of Russia were thwarted after twenty years of war with Sweden and the Ottoman Empire. The Great Northern War ended with Denmark surrendering Norway to King Frederick I of Sweden, and Russia becoming a Swedish client state. Meanwhile, the Swedes' Ottoman and Crimean allies extended their control over all of the Ukraine and until the Southern Volga -- including Saray-Batu (formerly Volgagrad), the capital of the Golden Horde, which fell to the Crimean Khanate. The Polish-Lithuanian Commonwealth fell further into a decline from which it would never recover, and the Western powers would not be able to intervene, as the War of the Spanish Succession would not end until 1721.
But what would have happened if Tsar Peter, and his Danish and Polish-Lithuanian allies, had been more successful?