President Donald Trump continues to push for a U.S. takeover of Greenland.

In the aftermath of WWII, American efforts to acquire the island ramped up, including a proposed swap that included oil-rich ...

It's a vast territory. Gracing the Arctic, much of it is frozen. It's sparsely populated. It holds vast natural resources.

Russia lost a war in Crimea in the 1850s, leaving the country deep in debt. To ease that burden, Russia cut a real estate deal with the U.S. government, selling its colony of Alaska to the Americans.