Until recently the most that people tended to know about cold and sparsely populated Greenland is that it is not small and also that it is not Iceland. It’s a frigid autonomous territory of Denmark, but self-governing.

President Trump isn’t the first U.S. politician to be interested in Greenland — not by a long shot.

Interest in buying Greenland has "popped up from time to time in American politics," Tom Høyem, Denmark's former minister to Greenland, told ABC News in an interview.