Louisiana Purchase (1803): How the United States Doubled in Size

The Louisiana Purchase was the agreement, dated 30 April 1803, by which France sold its vast Louisiana territory west of the Mississippi River to the United States for about 15 million dollars. Negotiated in Paris by envoys of President Thomas Jefferson with ministers of Napoleon Bonaparte, it roughly doubled the size of the young republic, secured the port of New Orleans and set the United States on a path of westward expansion with profound consequences for Native nations.

Background: a territory changing hands and a crisis at New Orleans

France had claimed the Mississippi basin since René-Robert Cavelier de La Salle travelled down the river in 1682 and named the region after Louis XIV. The French built forts and trading posts and in 1718 laid out the town of New Orleans near the river’s mouth. After defeat in the Seven Years’ War, France gave Louisiana west of the Mississippi, together with New Orleans, to its ally Spain in 1762–1763.

For the next four decades Spain governed Louisiana as a thinly settled buffer protecting Mexico. Meanwhile American farmers poured across the Appalachian Mountains into Kentucky, Tennessee and Ohio. Because roads over the mountains were poor, their crops travelled by flatboat down the Ohio and Mississippi to New Orleans. Pinckney’s Treaty of 1795 gave Americans the “right of deposit”, allowing them to store goods at New Orleans for shipment overseas without paying duties.

In 1800 Napoleon, then First Consul of France, persuaded Spain to return Louisiana in the secret Treaty of San Ildefonso, confirmed in 1801. He dreamed of reviving a French empire in the Americas, with Louisiana supplying food and timber to the rich sugar colony of Saint-Domingue in the Caribbean.

News of the secret retrocession alarmed Jefferson, who wrote in 1802 that whoever possessed New Orleans was the natural enemy of the United States. A weak Spain on the Mississippi was tolerable; a powerful, ambitious France was not. Then, in October 1802, the Spanish intendant at New Orleans suspended the American right of deposit, causing anger in the western states and talk of war.

Jefferson chose diplomacy. Robert R. Livingston, the American minister in Paris, had already been trying to buy New Orleans. In January 1803 Jefferson sent James Monroe to France as envoy extraordinary, with authority to offer up to about 10 million dollars for New Orleans and the Floridas, which the Americans wrongly believed might also be included in the transfer to France. Congress quietly approved 2 million dollars for the purpose.

Why Napoleon decided to sell

Napoleon’s American plans collapsed in the Caribbean. In 1802 he sent a large army under his brother-in-law Charles Leclerc to reassert control over Saint-Domingue, where the Haitian Revolution had ended slavery. The expedition met fierce resistance from Black and mixed-race soldiers, and yellow fever devastated the French troops. Leclerc himself died in November 1802, and tens of thousands of French soldiers and sailors perished.

Without Saint-Domingue, Louisiana lost much of its value to France. War with Britain was about to resume after the brief Peace of Amiens, and the Royal Navy could easily seize New Orleans. Napoleon needed money for the coming war and calculated that selling Louisiana would strengthen the United States as a rival to Britain while denying the territory to the British.

On 11 April 1803 the French foreign minister, Charles-Maurice de Talleyrand, surprised Livingston by asking what the United States would pay for the whole of Louisiana. Napoleon placed the negotiation in the hands of his finance minister, François Barbé-Marbois, who had lived in the United States and was sympathetic to it.

Negotiation, ratification and transfer

Monroe arrived in Paris on 12 April, and over the following weeks he, Livingston and Barbé-Marbois haggled over the price. The envoys had no authority to buy so vast a territory, and communication with Washington took weeks by sea, so they decided to accept the offer on their own responsibility.

The final agreement consisted of three documents: a treaty of cession and two conventions dealing with payment. They were dated 30 April 1803 and signed in the first days of May. The United States agreed to pay 60 million francs (about 11.25 million dollars) and to take over up to 20 million francs (about 3.75 million dollars) of claims that American citizens held against France. The money was raised by issuing American bonds, handled by the banking houses of Baring Brothers in London and Hope and Company in Amsterdam.

The treaty did not define the boundaries clearly. It simply transferred Louisiana with the same extent it had under Spain and France. When Livingston asked about the borders, Talleyrand reportedly replied that the Americans had made a noble bargain and would make the most of it.

The treaty raised constitutional doubts. Jefferson, who generally favoured a strict reading of the Constitution, believed it gave no clear power to acquire foreign territory and drafted an amendment to authorise the purchase. Warned that Napoleon might change his mind, he set the amendment aside. Some Federalists in New England opposed the treaty, fearing that new western states would weaken their region’s influence, but the Senate ratified it on 20 October 1803 by 24 votes to 7.

Spain protested that France had promised never to give Louisiana to a third power, but it could do nothing. On 30 November 1803 the Spanish governor formally handed Lower Louisiana to the French prefect Pierre Clément de Laussat at New Orleans. Twenty days later, on 20 December, Laussat transferred it to American commissioners William C. C. Claiborne and General James Wilkinson in the Cabildo, the government building on the city’s main square. Upper Louisiana was transferred at St. Louis on 9–10 March 1804.

Key people

• Thomas Jefferson (1743–1826), third president, who pursued the purchase despite his constitutional misgivings and then sent explorers to survey it.
• Napoleon Bonaparte (1769–1821), First Consul of France, who decided to sell after the failure of his Caribbean plans.
• Robert R. Livingston (1746–1813), American minister to France and co-signer of the treaty.
• James Monroe (1758–1831), Jefferson’s special envoy and later fifth president.
• François Barbé-Marbois (1745–1837), French finance minister who negotiated for France.

Consequences for the United States

The purchase added roughly 828,000 square miles to the country, land that would eventually form all or part of 15 states, from Louisiana and Arkansas to Montana and Minnesota. Control of the Mississippi and New Orleans secured the trade of the western farmers and removed the threat of a strong European power on the nation’s flank.

Jefferson moved quickly to learn about his new territory. The Lewis and Clark Expedition set out in 1804 to explore the Missouri River and find a route to the Pacific, and other expeditions followed along the Red and Arkansas rivers. In 1804 Congress organised the southern part as the Territory of Orleans, which became the state of Louisiana on 30 April 1812, exactly nine years after the treaty’s date.

The vague borders caused disputes for years. The United States claimed that part of Spanish West Florida was included and occupied it in stages from 1810. The Adams–Onís Treaty of 1819 with Spain finally fixed the western boundary, and the Convention of 1818 with Britain set the northern border along the 49th parallel to the Rocky Mountains.

Consequences for Native nations

The land France sold was not empty. It was home to many Native nations, including the Osage, Quapaw, Caddo, Pawnee, Omaha, Mandan, Lakota, Cheyenne, Crow and Blackfeet, most of whom had never acknowledged French or Spanish rule. In practice, France sold only its claim to sovereignty and its right, against other European powers, to acquire Native land.

Over the following century the United States extinguished Native title through treaties, purchases, pressure and war. The new western lands also became a destination for eastern nations forced from their homelands under the Indian Removal Act of 1830, as on the Trail of Tears. The expansion of slavery into the new territory, meanwhile, became one of the most divisive questions in American politics, leading to the Missouri Compromise of 1820.

Myths and facts

Myth: The United States bought the land outright. The purchase transferred France’s claim against other colonial powers, not ownership of land held by Native peoples. Much more money was later paid, and much violence used, to acquire actual control.

Myth: The deal was a carefully planned American goal. Jefferson’s envoys were instructed to buy New Orleans and, if possible, the Floridas. The offer of the entire territory came from France and took the Americans by surprise.

Myth: The purchase cost “three cents an acre” and nothing more. The commonly quoted figure of under three cents an acre reflects the price paid to France. With interest on the bonds, the total cost to the treasury was well over 20 million dollars, and later payments to Native nations added much more.

By the numbers

Timeline

• 1800, 1 October: Secret Treaty of San Ildefonso returns Louisiana from Spain to France.
• 1802, October: Spain suspends the American right of deposit at New Orleans.
• 1803, January: Jefferson appoints James Monroe as envoy extraordinary to France.
• 1803, 11 April: Talleyrand asks Livingston what the US would pay for all of Louisiana.
• 1803, 30 April: Date of the treaty and conventions of cession, signed in early May.
• 1803, 20 October: US Senate ratifies the treaty by 24 votes to 7.
• 1803, 20 December: France transfers Lower Louisiana to the United States at New Orleans.
• 1804, 9–10 March: Upper Louisiana is transferred at St. Louis.
• 1812, 30 April: Louisiana becomes the eighteenth US state.

Why it matters

The Louisiana Purchase turned the United States from an Atlantic republic into a continental power. It secured the Mississippi for American trade, opened the way for expansion to the Pacific and shaped the nation’s politics for decades. It also began a long and often violent process of dispossession for the Native nations of the Great Plains and the Mississippi valley, a legacy that remains part of its history.