The Louisiana Purchase was an 1803 agreement in which France transferred to the United States a vast territory within its North American
empire known as Louisiana, about 530 million acres lying between the
Mississippi and Missouri Rivers. The United States paid France $15 million, or about 3 cents per acre. The lands transferred in the Louisiana
Purchase comprise nearly one-quarter of the territory of the present-day United States.
French Louisiana
When Thomas Jefferson (1743–1826; served 1801–9) became president in 1801, Louisiana was a vast and vaguely defined territory. Notable
mainly because it included the important port city of New Orleans,
Louisiana had originally been part of French North America. In 1763,
France had ceded Louisiana to Spain. In the spring of 1801, Jefferson
received word of a series of secret agreements between French emperor
Napoleon Bonaparte (1769–1821) and Spain, in which Spain had
restored the Louisiana region to France. Jefferson viewed this transfer
with alarm because a powerful French colony in control of the mouth of
the Mississippi River threatened American shipping and trade as well as westward expansion.
When French officials took over Louisiana, they refused to allow
U.S. goods to be stored at the port of New Orleans. To reach Atlantic
markets, farmers and merchants in the Tennessee River and Ohio River
valleys needed to ship their goods down the Mississippi. Some unhappy
Americans supported war with France to gain this important port.
Jefferson, hoping to avoid conflict, sent his minister to France, Robert
Livingston (1746–1813), and later, James Monroe (1758–1831), to
Paris. The president instructed them to seek France’s guarantee that
Americans could use the port at New Orleans and ship goods to the
Atlantic from the Mississippi. Failing that, the ministers were instructed
to negotiate the purchase of New Orleans and western Florida from
France, limiting the amount they could spend to $9 million.
Napoleon had planned to create a large empire in North America,
with its base on the French colonial island of Hispaniola (present-day
Dominican Republic and Haiti). Just as the American ministers were
preparing to negotiate over Louisiana in 1801, however, an incident in
the Caribbean changed the French emperor’s mind. In the sugar colony
of Santo Domingo, on Hispaniola, an army of black slaves led by
Toussaint-Louverture (c. 1743–1803) seized power, successfully overwhelming the French. The revolution on Hispaniola made Napoleon
realize it was too costly and difficult to maintain distant French colonies
in the Americas. He quite suddenly decided to unload all of the vast territory called Louisiana.
The purchase is signed
Livingston and Monroe did not hesitate in agreeing to purchase the
entire region, despite the fact that their instructions called only for
acquiring New Orleans and western Florida. The two men knew that the
United States and its citizens desperately wanted land to expand the new
country; this was an opportunity not to be missed. On April 30, 1803,
Livingston, Monroe, and a French negotiator initialed agreements transferring the entire Louisiana region to the United States in exchange for
$11.25 million. In addition, the United States assumed $3.75 million in
claims of U.S. citizens against France. Yet the deal did not clearly define
Louisiana, only describing it as the land that France had possessed before
1763. The French ministers were evasive about the region’s limits.
Signing the agreement was not as easy for Jefferson. He understood
that the acquisition of Louisiana had enormous implications for the
nation’s development, setting the stage for future increased trade and
westward expansion. If Jefferson accepted the offer, the United States
would double in area, and both banks of the Mississippi River would be
under American control. But he had no clear constitutional authority to
make such a purchase. Besides, there was opposition. New England
Federalists feared that adding the huge region would tilt the balance of
political power in the direction of western and southern states and were
ready to debate the acquisition at length. Jefferson pondered a constitutional amendment to authorize the purchase. But given the dim prospects
of approval and the unlikelihood that Napoleon’s offer would wait,
Jefferson decided to go ahead with the deal. Despite the questionable constitutionality of purchasing the region, Congress approved it as well.
U.S. Louisiana
In January 1803, three months before the deal was made, Jefferson had
requested congressional funding for a cross-continental survey of the
Louisiana region and beyond. The Lewis and Clark Expedition from
1804 to 1806, led by Meriwether Lewis (1774–1809) and William Clark
(1770–1838), produced the first scientific and economic information
about this land that had been purchased literally sight-unseen by the
United States. The Lewis and Clark Expedition became the basis of a
U.S. claim extending the limits of the Louisiana Territory as far west as
the Columbia River region and as far south as western Florida and Texas.
Spanish objections, first over the legality of France’s sale of the territory
and then over its boundaries, resulted in a dispute lasting until the signing of the Adams-Onis (or Transcontinental) Treaty in 1819, by which
the United States gained all of Florida and a southern strip of Alabama
and Mississippi, while Spain retained its claim to the Southwest, which
was roughly the area of present-day Texas, New Mexico, Colorado,
Utah, Arizona, Nevada, and California.
The acquisition of Louisiana in 1803 virtually doubled the territorial extent of the United States. Out of the Louisiana Territory eventually emerged the states of Louisiana, Arkansas, Iowa, Missouri,
Nebraska, North Dakota, South Dakota, Oklahoma, and parts of
Kansas, Minnesota, Colorado, Montana, and Wyoming. Through this
purchase, the United States became a continental power, controlled the
continent’s main navigation routes, and became the owner of vast new
resources. These combined assets promised the young nation greater
economic independence from Europe and set a precedent for future territorial expansion all the way to the Pacific Ocean.
While the cost of the new territory amounted only to about 3 cents
per acre, in the long run the United States paid a steep price. The question of whether or not to allow slavery in the new land was a major bone
of contention between the North and South, necessitating the Missouri
Compromise of 1820 and its eventual repeal in the Kansas-Nebraska
Act of 1854. In this respect, the Louisiana Purchase can be understood
to be one of the long-term causes of the American Civil War (1861–65).