The Louisiana Purchase: Doubling America’s Size
The United States bought the Louisiana Territory from France in 1803. Learn about the Louisiana Purchase and how it doubled America’s size.
What territory did the United States buy from France in 1803? The Louisiana Territory or Louisiana. In 1803, President Thomas Jefferson purchased approximately 828,000 square miles of territory from France for $15 million. This Louisiana Purchase doubled the size of the United States, adding land that would become all or part of 15 states. It was one of the most important land acquisitions in American history, opening the West to American settlement and making the United States a continental power.
For the citizenship test, you need to know that the United States bought the Louisiana Territory (or Louisiana) from France in 1803.
The Essential Facts
For the citizenship test, remember: The United States bought the Louisiana Territory (or Louisiana) from France in 1803.
Key facts about the Louisiana Purchase:
Year: 1803
Seller: France (Napoleon Bonaparte)
Buyer: United States (President Thomas Jefferson)
Price: $15 million (about 3 cents per acre)
Size: About 828,000 square miles
Effect: Doubled the size of the United States
Future States: All or part of 15 current states
This purchase was one of the most significant events in American history.
What Was the Louisiana Territory?
The Louisiana Territory was vast:
Size: Approximately 828,000 square miles – from the Mississippi River to the Rocky Mountains, from the Gulf of Mexico to the Canadian border
Today’s States (all or part):
- Louisiana
- Arkansas
- Missouri
- Iowa
- Minnesota
- North Dakota
- South Dakota
- Nebraska
- Kansas
- Oklahoma
- Montana
- Wyoming
- Colorado
- New Mexico (small part)
- Texas (disputed portion)
Not Just Louisiana State:
The Louisiana Territory was much larger than the current state of Louisiana. It included most of the Great Plains and stretched to the Rocky Mountains.
Original Inhabitants:
Native American tribes lived throughout the territory: Sioux, Cheyenne, Osage, Pawnee, and many others. The purchase ignored their presence and claims to the land.
Why France Sold Louisiana
France sold Louisiana for several reasons:
Napoleon’s Plans Changed:
French Emperor Napoleon Bonaparte originally wanted to rebuild France’s North American empire. He envisioned Louisiana as the agricultural base feeding French sugar colonies in the Caribbean (especially Haiti).
Haitian Revolution:
Enslaved people in Haiti revolted (1791-1804), defeating French attempts to reconquer the island. Without Haiti, Louisiana lost its strategic value to France.
European Wars:
France was fighting wars in Europe against Britain and other powers. Napoleon needed money for military campaigns more than he needed distant American territory.
Impossible to Defend:
France couldn’t defend Louisiana from British naval power or American expansion. If war came, Britain would likely seize Louisiana anyway.
American Threat:
Americans were already settling west of the Appalachians. Napoleon realized he couldn’t stop American expansion into Louisiana.
Ready Buyer:
The United States wanted Louisiana, especially New Orleans. Selling to America was better than losing it to Britain.
Napoleon decided selling Louisiana for quick cash was smarter than trying to hold it.
Why the United States Wanted Louisiana
The United States had compelling reasons to buy:
New Orleans:
New Orleans controlled the Mississippi River’s mouth. Western farmers shipped crops down the Mississippi to New Orleans, then to markets. Whoever controlled New Orleans controlled western trade.
Spanish Threat:
Spain had controlled Louisiana until 1800, when it secretly returned Louisiana to France. Americans feared France would be a more dangerous neighbor than weak Spain.
Western Expansion:
Americans were already moving west. Acquiring Louisiana would open vast territories for settlement and remove foreign powers from America’s borders.
Navigation Rights:
Americans needed guaranteed rights to navigate the Mississippi River and use New Orleans port. Ownership was more secure than treaties.
National Security:
Having a major European power (France) controlling the Mississippi Valley threatened American security. Purchase removed this threat.
Opportunity:
When Napoleon offered to sell all of Louisiana (not just New Orleans), Jefferson saw an unprecedented opportunity to expand the nation.
Jefferson’s Dilemma
Thomas Jefferson faced a constitutional problem:
Strict Construction:
Jefferson believed in strict interpretation of the Constitution – the federal government should only exercise powers explicitly granted by the Constitution.
No Constitutional Authority:
The Constitution doesn’t explicitly grant power to purchase foreign territory. By his own principles, Jefferson lacked authority to buy Louisiana.
Practical Necessity:
The opportunity was too good to pass up. Louisiana would double America’s size and secure western trade routes.
The Decision:
Jefferson decided national interest outweighed constitutional concerns. He purchased Louisiana despite his constitutional doubts.
Philosophical Compromise:
Jefferson rationalized that the treaty power allowed territorial acquisition. He submitted the treaty to the Senate, which approved it.
Legacy:
Jefferson’s Louisiana Purchase showed even strict constructionists would use broad federal power when necessary. It expanded presidential power and federal authority.
The Negotiation
The purchase happened quickly:
Monroe and Livingston:
Jefferson sent James Monroe and Robert Livingston to France to negotiate purchasing New Orleans and West Florida for up to $10 million.
Napoleon’s Surprise Offer:
Instead of just New Orleans, French foreign minister Talleyrand offered all of Louisiana. He asked: “What will you give for the whole?”
Quick Decision:
Monroe and Livingston lacked authority to purchase all Louisiana, but the opportunity was too good to pass up. They negotiated quickly before Napoleon changed his mind.
The Deal:
- Price: $15 million ($11.25 million for territory, $3.75 million to settle American claims against France)
- Signed: April 30, 1803
- American negotiators exceeded their instructions but made the greatest land deal in history
Senate Approval:
The Senate ratified the treaty in October 1803 by 24-7 vote.
Transfer:
France formally transferred Louisiana to the United States on December 20, 1803, in New Orleans.
Significance of the Louisiana Purchase
The purchase transformed America:
Doubled U.S. Size:
The United States went from about 890,000 square miles to 1.7 million square miles overnight.
Removed European Power:
Eliminated France from North America, reducing threats to American security.
Opened the West:
Made westward expansion possible. Americans could now settle from the Atlantic to the Rocky Mountains.
Agricultural Expansion:
Added vast fertile lands for farming and ranching.
Natural Resources:
Acquired territories rich in natural resources: furs, minerals, timber, oil (discovered later).
Future States:
Provided land for 15 future states, shaping the nation’s geography and political structure.
Continental Power:
Made the United States a continental power stretching across North America.
Manifest Destiny:
Encouraged belief in America’s “manifest destiny” to expand across the continent.
Best Real Estate Deal:
At about 3 cents per acre, arguably the best real estate deal in history.
Exploration: Lewis and Clark
After purchasing Louisiana, Jefferson wanted to explore it:
The Expedition:
Jefferson sent Meriwether Lewis and William Clark to explore the Louisiana Territory and beyond to the Pacific Ocean (1804-1806).
Purposes:
- Map the territory
- Find water route to Pacific (Northwest Passage)
- Study plants, animals, and geography
- Establish relations with Native tribes
- Assert American claims to the region
Journey:
The expedition traveled up the Missouri River, across the Rockies, and down the Columbia River to the Pacific Ocean. They returned in 1806 after traveling over 8,000 miles.
Sacagawea:
A Shoshone woman who served as guide and interpreter. Her presence helped peaceful relations with tribes.
Discoveries:
- No Northwest Passage existed
- Mapped vast territories
- Documented hundreds of plant and animal species
- Established American claims to Oregon Territory
- Proved the vast scale of the West
Legacy:
Lewis and Clark opened the West to American knowledge and eventual settlement.
Opposition to the Purchase
Not everyone supported the Louisiana Purchase:
Federalist Opposition:
Federalist Party (strongest in New England) opposed the purchase:
- Worried western states would diminish New England’s political power
- Feared expansion would make the country too large to govern
- Questioned constitutionality
- Didn’t want to spend $15 million
Constitutional Concerns:
Even some who wanted Louisiana questioned whether the Constitution allowed the purchase.
Slavery Question:
Debates emerged about whether Louisiana territories would allow slavery. This foreshadowed sectional conflicts leading to the Civil War.
Native American Displacement:
The purchase ignored Native American inhabitants. Tribes would be displaced as Americans settled Louisiana.
Despite opposition, the purchase proceeded and proved overwhelmingly beneficial to the United States.
Long-Term Impact
The Louisiana Purchase had lasting effects:
Westward Migration:
Americans streamed west to settle Louisiana lands. This migration shaped American culture and character.
Slavery Extension:
Some Louisiana Territory became slave states (Missouri, Arkansas, Louisiana), extending slavery westward and intensifying sectional conflict.
Native American Displacement:
Plains tribes were pushed off their lands as Americans settled. This continued the tragic pattern of Native American dispossession.
Agricultural Development:
The Great Plains became America’s breadbasket, producing grain that fed the nation and world.
Economic Growth:
Natural resources from Louisiana enriched America and fueled economic development.
Political Balance:
New states from Louisiana affected the balance between North and South, free and slave states.
Continental Nation:
The purchase started the process that made the United States a continental nation spanning from Atlantic to Pacific.
Connections to Other Topics
Understanding the Louisiana Purchase connects to Thomas Jefferson’s presidency. The purchase was Jefferson’s greatest achievement despite contradicting his constitutional principles.
The purchase relates to westward expansion. It provided the land base for America’s growth from 13 states to 50 and the settlement of the West.
The Louisiana Purchase also connects to Native American history. Acquisition of Louisiana meant displacing Native tribes who had lived there for thousands of years.
For more on Jefferson, see our article on Thomas Jefferson in the uscis-questions category. To understand westward expansion, read about American territorial growth. To learn about exploration, explore articles on Lewis and Clark.
Top 10 Frequently Asked Questions
What did the U.S. buy from France in 1803?
The Louisiana Territory (or Louisiana). This is the answer for the citizenship test.
How much did it cost?
$15 million (about 3 cents per acre) – one of history’s greatest real estate deals.
How big was it?
About 828,000 square miles – roughly doubling the size of the United States.
Which states came from Louisiana Purchase?
All or part of 15 states: Louisiana, Arkansas, Missouri, Iowa, Minnesota, North Dakota, South Dakota, Nebraska, Kansas, Oklahoma, Montana, Wyoming, Colorado, and parts of New Mexico and Texas.
Why did France sell?
Napoleon needed money for European wars, couldn’t defend Louisiana, and lost his Caribbean colonies, making Louisiana less valuable.
Did Jefferson have authority to buy it?
Questionably. The Constitution doesn’t explicitly grant power to purchase territory. Jefferson proceeded anyway based on treaty power.
Who explored Louisiana after purchase?
Lewis and Clark led the most famous expedition (1804-1806), traveling to the Pacific and back.
Did anyone live in Louisiana Territory?
Yes – hundreds of thousands of Native Americans and some French and Spanish settlers. The purchase ignored Native claims.
Was the purchase controversial?
Yes – Federalists opposed it, and constitutional questions arose. But it proved highly beneficial.
What should I memorize for the citizenship test?
The United States bought the Louisiana Territory (or Louisiana) from France in 1803. Know it doubled the size of the United States. This is sufficient for the test.