Purchase of Alaska
Just looked it up
Answer:
He is referring to Europe's penchant for imperialism
Explanation:
Imperialism is when one or more countries want to extend their own influence over other countries or regions either through land expansion or by strong cultural influence (sometimes both). Countries like Great Britain, for example, are significant models of this idea. Europe was a hotbed of imperialism and this led to many conflicts and wars.
Great plains is known for the mountains
