The historical highlights: In the 15th century for the Treaty of Tordesillas, global superpowers Portugal and Spain sat down with a map of the world (as they knew it in the 1400s) and drew a line down the middle. Portugal got everything on the left, Spain on the right. Even Steven, right? Not quite. Once they decided to actually look at their new “empire,” Portugal found it basically had nothing (well, besides Brazil), while Spain had pretty much the entire world (you know, Europe, Asia, Russia…).

It taught Portugal a harsh lesson: Approaching land deals the way the kids in “Family Circus” deal with sharing toys is not a viable global expansion strategy.

Real estate update: Granted, Portugal botched this deal at the table, but it’s not quite as bad as it sounds. According to David Reiss, a professor at Brooklyn Law School and research director for the Center for Urban Business Entrepreneurship, the treaty was “heavily modified afterward” to give Portugal more land to the west, including control over most of the Indian Ocean.

Still, in the end, no one won: Both empires eventually shrank back to the size you see today. If Spain won anything, it’s the language war: Most of Central America speaks Spanish, while only Brazil parlays in Portuguese.

America goes through a major growth spurt

The historical highlights: In 1803, America made its historic Louisiana purchase, buying 828,000 square miles of land from France for $15 million—roughly the catering budget of an “Avengers” flick today. That territory gave the fledgling nation a hell of a growth spurt, adding land that would become 15 Midwestern states from Arkansas to, of course, Louisiana.

Real estate update: It was a lot of land, and it cost a lot at the time. But it was totally worth it. “You got New Orleans, so right there it was a good deal,” says Reiss. “If you look at the home sales in New Orleans today, $15 million is the price of just the top four most expensive houses combined.”

The Alaskan ‘oil rush’

The historical highlights: In 1856, Russia negotiated with U.S. Secretary of State William Seward to sell Alaska for about 2 cents per acre, or $7.2 million. The purchase was derided, and the American people quickly dubbed Alaska “Seward’s Folly.”

Real estate update: Most people think that the measly $7 mill we spent on Alaska is pocket change compared to the gushing vats of cash funneling into the U.S. through the Alaska oil pipeline, right? Not exactly.

“We think of Alaska and its pipeline, and we think it’s a great deal,” says Reiss. “But economists have deduced that the pipeline earns the government less than it costs to govern Alaska, so it’s a net loss. Calling it ‘Seward’s Folly’ makes sense.”

$24 for … Manhattan?

The historical highlights: It’s one of the oldest stories in our history—Savvy Dutch settlers, preying on the naiveté of the Canarsie Indians, bought all of what would become Manhattan for $24, less than the price of a sweater from a Times Square Forever 21.

Real estate update: True, New York City is estimated to be worth $802.4 billion today, and Manhattan is its busiest hub. However, before you express outrage about those poor Indians, consider this: It was the Dutch who got conned. You see, the Canarsie Indians who brokered the deal didn’t live in Manhattan. Sure, they’d hop over there to party with the Manhattoes tribe, but it wasn’t their home and they certainly had no right to sell.

“The common story is that the Europeans swindled the natives,” says Reiss. “But it does look like the other way around.” (The Manhattoes, however, are another story.)

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Man sells the moon

The historical highlights: In 1967, the United Nation Outer Space Treaty stated in regard to our moon: “No nation by appropriation shall have sovereignty or control over any of the satellite bodies.” In 1980, a Nevada resident named Dennis Hope came to the conclusion that the treaty forbade nations from owning the moon but not individuals. So he wrote a letter to the U.N. saying he was taking ownership and that it should contact him if it had any issue with that. The U.N. did not respond, and he’s been selling moon acreage ever since. Hope claims to have sold over 600 million acres, with the largest going for over $13 million.

Real estate update: If he really has those checks in hand, then Hope is a genius and this is indeed a very lopsided deal—he’s selling uninhabited land that will be completely inaccessible in the lifetimes of the buyers. Not that we should necessarily applaud him for it.

At worst, “I’d classify him as a huckster,” says Reiss. “And it appears his interpretation of the law is incorrect. The fact that the government hasn’t responded to his letter doesn’t give him rights to the land.” So, even if he does have all that money, it could get him in a whole lot of trouble.