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The Louisiana Purchase, signed on April 30, 1803, doubled the size of the United
1803 Event

April 30

Louisiana Purchase: America Doubles in Size for $15 Million

The Louisiana Purchase, signed on April 30, 1803, doubled the size of the United States for $15 million, roughly four cents per acre. Napoleon needed cash to fund his European wars and had just lost his most valuable Caribbean colony, Saint-Domingue (Haiti), to a slave revolt led by Toussaint Louverture. American negotiators Robert Livingston and James Monroe had been authorized to spend $10 million for New Orleans alone; Napoleon's offer of the entire 828,000-square-mile territory stunned them. Jefferson worried the Constitution did not authorize such a purchase but proceeded anyway, reasoning that the national interest outweighed strict constructionism. The territory encompassed all or part of 15 future states and contained the Mississippi River system, which controlled commerce for the entire interior of the continent.

April 30, 1803

223 years ago

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