The Louisiana Purchase, the western half of the Mississippi River basin purchased in 1803 from France at less than three cents per acre for 828,000 square miles, was the greatest land bargain in U.S. history. The purchase doubled the size of the United States, strengthened the country materially and strategically, provided westward expansion, and confirmed the doctrine of implied powers of the federal Constitution.

The Louisiana Territory Under Spanish And French Rule

Explorations and scattered settlements in the 17th and 18th centuries had given France control over the river. In 1762 during the Seven Years’ War, France ceded Louisiana west of the Mississippi River to Spain. French power grew under the military leadership of Napoleon Bonaparte, and on October 1, 1800, Napoleon convinced King Charles IV of Spain to return Louisiana to France.

At the end of the 18th century, Americans streamed westward into the valleys of the Cumberland, Tennessee, and Ohio rivers. The new settlers depended on their right to use the Mississippi River freely and to ship their exports at New Orleans. In 1802, Spain revoked the United States' right to ship goods through the mouth of the Mississippi River without paying duty and also the right of deposit. President Jefferson was confronted with potential problems if Spain blocked access to the Gulf of Mexico.

Negotiations Between France And The United States

Jefferson instructed Robert R. Livingston, the U.S. minister at Paris, to try to purchase New Orleans. Livingston was not able to make much progress, even when hinting to France that the United States might tighten its relationship with French enemy—Great Britain.

There are good reasons to believe Napoleon offered the entire Louisiana Territory for sale to the United States in 1803 for many reasons: French failure in the island of Hispaniola, the imminence of renewed war with Great Britain, and financial problems. In 1803 James Monroe arrived in Paris to take over negotiations, which concluded swiftly.

Defining The Purchase

The Louisiana Territory, in the form France had received it from Spain, was sold to the United States. The United States agreed to pay $11,250,000 and assumed claims of its citizens against France in the amount of $3,750,000. Interest payments made the total price $27,267,622.

Precisely what the United States had purchased was unclear. But before the United States could establish fixed boundaries to Louisiana there arose a basic question concerning the constitutionality of the purchase. Did the Constitution of the United States provide for an act of this kind? President Jefferson, in principle a strict constructionist, thought that an amendment to the Constitution might be required. After due consideration the Senate approved the treaty by a vote of 24 to 7.

Source: Louisiana Purchase #2
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