Louisiana Purchase

The Louisiana Purchase (French: Vente de la Louisiane "Sale of Louisiana") was the acquisition by the United States of America in 1803 of 828,000 square miles (2,140,000 km2) of France's claim to the territory of Louisiana. The U.S. paid 50 million francs ($11,250,000) plus cancellation of debts worth 18 million francs ($3,750,000), for a total sum of 15 million dollars (less than 3 cents per acre) for the Louisiana territory ($233 million in 2011 dollars, less than 42 cents per acre).

The Louisiana territory encompassed all or part of 15 current U.S. states and two Canadian provinces. The land purchased contained all of present-day Arkansas, Missouri, Iowa, Oklahoma, Kansas, and Nebraska; parts of Minnesota that were west of the Mississippi River; most of North Dakota; most of South Dakota; northeastern New Mexico; northern Texas; the portions of Montana, Wyoming, and Colorado east of the Continental Divide; Louisiana west of the Mississippi River, including the city of New Orleans; and small portions of land that would eventually become part of the Canadian provinces of Alberta and Saskatchewan.

France controlled this vast area from 1699 until 1762, the year it gave the territory to its ally Spain. Under Napoleon Bonaparte, France took back the territory in 1800 in the hope of building an empire in North America. A slave revolt in Haiti and an impending war with Britain, however, led France to abandon these plans and sell the entire territory to the United States, who had originally intended only to seek the purchase of New Orleans and its adjacent lands.

The purchase of the territory of Louisiana took place during the presidency of Thomas Jefferson. At the time, the purchase faced domestic opposition because it was thought to be unconstitutional. Although he agreed that the U.S. Constitution did not contain provisions for acquiring territory, Jefferson decided to go ahead with the purchase anyway in order to remove France's presence in the region and to protect both U.S. trade access to the port of New Orleans and free passage on the Mississippi River.