ON THIS DAY IN 1803, FRANCE OFFICIALLY TURNED OVER LOUISIANA TO THE UNITED STATES AT A FLAG-RAISING CEREMONY IN NEW ORLEANS: The Louisiana Purchase added 828,000 square miles to the United States as well as control of the Mississippi River (which made already-existing territories in Mississippi and Ohio River watersheds that much more valuable). We got it for the bargain price of 50 million francs plus the cancellation of debts worth 18 million francs. At the time, that would have been $15 million–a bargain, even then, for such a vast territory.

The whole thing took President Jefferson a bit by surprise. He had wanted negotiate the sale of New Orleans and its environs. But on April 11^, 1803, Foreign Minister Talleyrand told the American minister to France Robert Livingston that Napoleon was willing to sell all of the Louisiana Territory. Truth be told, Napoleon had abandoned his earlier plans for North America and needed to raise some money quickly for his other activities.

Jefferson worried that as President he did not have the authority to commit to such a deal. But his advisors told him he’d be crazy to turn it down. So he took it. The rest is history.