Ice ice baby.
“In the late 1700s, Russia had been on a mission of imperial conquest for 600 years. One of the main reasons is because of ice, which makes Siberia inhospitable, so it was relatively easy for Russia to keep moving eastward until it reached the end of Asia. And then, like the paleolithic people who crossed the Bering Strait during the last glaciation, Russia jumped the strait and continued its conquest, into present day Alaska.But if you own Alaska in the 1800s, you don’t really own anything. It’s a bunch of mountains and snow. What can you get from there?”
https://unchartedterritories.tomaspueyo.com/p/how-ice-sculpted-canada