Expansion Westward: The History of the Louisiana Purchase

The Louisiana Purchase was a land treaty that doubled the size of the United States, and it served as the first American foray into the West.

Apr 9, 2023By Madison Whipple, BA History w/ Spanish minor
history of louisiana purchase expansion westward


In 1803, the United States took possession of the Louisiana Purchase, a territory of approximately 827,000 square miles. In a treaty with France, the United States purchased the land for $15 million, which today equates to an astounding $395 million. Though most famous for the expedition of Lewis and Clark, the Louisiana Purchase enabled an era of expansion, and the concept of “Manifest Destiny” was born, all stemming from this purchase. It forever changed the geography and the mentality of the United States government and citizens.


Background of the Louisiana Territory & its Owners

portrait thomas jefferson and emperor napoleon bonaparte
Portrait of Thomas Jefferson by Gilbert Stuart via the Bowdoin College Museum of Art; with Portrait of Emperor Napoleon Bonaparte by Jacques-Louis David, 1812, via the National Gallery of Art, Washington DC


After losing the French and Indian War, France had to cede its North American territories. This meant that in 1762, Spain came to possess all of Louisiana west of the Mississippi River and, importantly, the city of New Orleans, a central hub for trade due to its situation at the delta of the Mississippi. The United States, eager to capitalize on this trade, forged the Pickney Treaty of 1795, which allowed American commerce access to navigation of the river, and use of New Orleans to deposit and transfer goods bound for trans-oceanic journeys.


The United States was in a good position regarding this territory. Thomas Jefferson even hoped that Spain would eventually give the land over permanently. However, this was brought to a halt by the ascension of Napoleon Bonaparte to the head of government in France. Napoleon was of the grandiose persuasion concerning territory. He was unhappy with France being pushed off the North American continent and intended to regain power there.


The Port of New Orleans by William James Bennett and Antoine Mondelli, 1841, via the National Gallery of Art, Washington DC


In 1802, Spain’s King Charles IV signed the Louisiana territory over to Napoleon and the French Empire, rendering the Pickney Treaty null and void. This, coupled with orders from the Spanish court system, revoked American access to the ports and warehouses of New Orleans. The United States was incensed, and the revocation sparked outrage among American citizens.

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In addition to outrage, Jefferson saw the foreboding outcome that could occur with France controlling the Mississippi River. Jefferson had been the ambassador to France for many years of his career, and he knew that he had to act quickly in the interests of his country to save them from attack.


While Jefferson sought more diplomatic means of dealing with the situation, citizens who lived in the west and the opposing Federalist party sought to regain their position in Louisiana by violent means. They advocated for war and secession of the western territories. Feeling pressure domestically and internationally, Jefferson sent James Monroe to Paris to serve as an additional minister to Robert Livingston.


Monroe Travels to Paris

portait of james monroe and robert livingston
Portraits of James Monroe and Robert Livingston, via Thomas Jefferson’s Monticello and Christie’s


James Monroe was a fellow Virginian who Thomas Jefferson served as a mentor to during Monroe’s years in law school at William and Mary. While he lived most of his life in Virginia, mainly as a neighbor to his friend and mentor Jefferson, he also accrued thousands of acres of land in Kentucky as a successful patriot in the Revolutionary War. This made Monroe familiar with the western territories of the United States and an advocate on behalf of the settlers therein.


In addition to his knowledge of the west, Monroe also served as minister to France from 1794 to 1797. Following his return to America, he served as the governor of Virginia from 1799 to 1802. Monroe then left office, intending to focus on the practice of law. Jefferson had different ideas for his old friend, so he called upon Monroe in 1803 to serve as a special envoy to France to purchase land from the French Empire.


Upon arriving in Paris, Monroe worked with colleague Robert Livingston to secure a deal to purchase the land east of Louisiana, including Florida. Jefferson and James Madison had instructed Monroe to advocate for this with no more than $10 million on the table. If he could not gain all of the territories the government wanted, he had to gain New Orleans for the Americans at least.


However, when Monroe arrived in Paris, he was unaware that the day earlier, the French government had made an offer. They wanted to sell the whole of the Louisiana territory.


negotiations for louisiana purchase
Negotiations for the Louisiana Purchase, via The New York Times


The French Empire was coming apart at the seams in the New World. While facing a slave revolt in the sugar colony of Saint Domingue (present-day Haiti), French soldiers were being wiped out by yellow fever. In addition, their zeal for capturing territory in the New World would almost surely cause war with Britain. France’s position was not nearly as strong as they thought it was.


Influenced by his finance minister, Napoleon offered the territory to the United States, preferring to focus on not losing the lucrative colony of Saint Domingue and unsure of Louisiana’s worth to their empire. Thus, negotiations between the countries began, and on April 30th, 1803, the United States and France reached a deal: the United States would own all 529 million acres that comprised the Louisiana Territory.


Brand New Owners 

louisiana purchase signing new orleans
The signing of the Treaty of the Louisiana Purchase, via the Architect of the Capitol


Jefferson later called the purchase “a fugitive occurrence.” The French emperor was willing to sell off any chance of staking his claim in the New World. Monroe and Livingston had doubled the size of their country for four cents per acre. This was over the president’s intended budget, but this price applied to more land than any of the United States dignitaries had imagined.


The news of the treaty was announced on July 4th, 1803, in Washington DC. The decision to purchase the land was a popular one with Americans. The seedling of Manifest Destiny was being planted, and many citizens could see themselves moving west.


However, despite the popularity of the acquisition, Jefferson and his cabinet now faced a more extensive set of issues: how could they justify the purchase under the Constitution, and how would they establish borders between the other colonized parts of North America that now surrounded the expanded contiguous United States?


Jefferson was known for subscribing to a very literal following of the Constitution. This presented a problem for him in purchasing the Louisiana Territory, as there was no Constitutional provision for a president’s ability to buy land from foreign powers. Jefferson saw the need for a new amendment to the Constitution: “It has not given it the power of holding foreign territory, and still less of incorporating it into the Union.” However integral Jefferson thought amending the Constitution would be, his cabinet saw it differently. Albert Gallatin, Jefferson’s Secretary of the Treasury, advised the president that the Constitution need not be amended, as the Louisiana Purchase fell under the provisions for making treaties.


map of louisiana purchase
Map of the Louisiana Purchase, via the Constitution Center


Relying on his cabinet’s opinions and interpretation of the Constitution, Jefferson sent the treaty to Congress, hoping the American people could see the benefits of the purchase and not the possible overreach of power. However, extra-Constitutional, he saw the purchase; he wanted the land more than he wanted to delay the process with an amendment. In a famous quote rationalizing the purchase, Jefferson said, “it is the case of a guardian, investing the money of his ward in purchasing an important adjacent territory; & saying to him when of age, I did this for your good.”


The problem with sending the treaty to the Senate for ratification was that Jefferson’s party, the Republicans, needed to convince the Federalist party that this expansion of executive power was necessary. It seems, however, that there needn’t be any worry, as, after only two days of debate, the Senate ratified the treaty by 24 votes for it and seven against it. The treaty was signed on October 31st, 1803. By November 30th, Spain had returned the territory to France, and after exactly one month, the United States formally came into possession of the land.


What was Next for the Louisiana Purchase? 

raising of american flag in new orleans
Raising of the American Flag over New Orleans by Thure de Thulstrup, 1903, via the Louisiana State Museum


The Louisiana Purchase was the first step in the United States’ expansion throughout the 19th century. By the end of the 1800s, the contiguous United States as we know it today was fully formed.


The Lewis and Clark Expedition of 1804 sparked movement westward as they explored the vast expanse of the Louisiana Purchase and beyond. However, the expansion also caused problems within the Union and emphasized the sectional divide between the North and South. The nation was held together as it expanded with a series of treaties and compromises between “free” and “slave” states. These precarious agreements would not stand the test of time, primarily based on the issue of slavery. In the end, civil war broke out as the expanded territories of the United States took sides on either side of the aisle.


In addition to the devolution into civil war, the United States also largely ignored the negative impact of treaties and acquisitions on the population who had already lived in these territories for thousands of years. Native Americans were eventually pushed onto reservations to make more room for white settlers. The Louisiana Purchase directly set this conflict with dozens of Native American tribes into motion and stole tribal lands for white pioneers.


The Louisiana Purchase established the United States’ ability to expand, but it also pitted people against one another. However problematic the expansion may have been, there is no denying that it changed the trajectory of the United States drastically. Without Napoleon’s cession in 1803, who could predict what the state of the Union would be today or how differently the nation’s history could have played out?

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By Madison WhippleBA History w/ Spanish minorMadison is a contributing writer with specialties in American and women’s history. She is especially interested in women’s history in the context of the American Civil War. In her free time, she enjoys going to museums, reading, and jogging.