If Russia hadn’t sold Alaska to the United States…what an interesting question of alternative history. Russia sold Alaska to the United States to prevent the British from getting it. That was a good idea for Britain with Alaska in their royal swag bag could have attacked Russia through Siberia across the Bering Strait.
By the year 1867 Russia promyshlenniki had taken most of the valuable furs that were easily accessible. The United States with its victory over the confederacy was still young and energetic with an expanding economy. Russia ended its own slavery-like institution of serfdom right after the ending of slavery in the U.S.A., and Britain had supported the southern states in the U.S. civil war; since Russia couldn’t very well afford to defend on Eastern and Western frontiers the Tsar probably thought it was better to have an ally with the U.S.A. rather than an opponent or worse- Brits, on the Eastern front.
European history and politics of an alternative nature based on real history is beyond the scope of my comment. I am no expert on European history either. One observes the Franco-Prussian war of 1870 and the growing power of neo-Germany that might have been a concern of Russia that was not misplaced. Germany defeated the Tsar’s Russian army in 1914 rather swiftly in 1914 leading the way to end Russian aristocracy and enabling the rise of the Red Bolsheviki (if I may use that term).
England and Germany were great industrial powers presenting a grim specter to the west of dark clouds of war sometime in the future. France actually made and donated the Statue of Liberty during the 1870s after the loss to Prussia. Alaska was a better gift providing needed cash.
I don’t believe the history of Alaska reasonably could have gone another way than it did unless at some earlier time Napoleon and Suvarov and become one force with Tsarina Catherine the Great and Napoleon able to get along and together dominate all of northern Eurasia extending to North America destroying the British in the process and letting Canada join the U.S.A. as five or six new states. In that case Russia would have probably kept Alaska and built a bridge or Causeway long ago affecting global warming earlier by stopping the flow of cool Arctic water south in that part of the world. Instead Napoleon spent his time avoiding a battle with Suvarov (who retired undefeated) and the rest is history.