The Louisiana Purchase: A Unit Study

On April 30, 1803, a treaty was signed between the United States of America and the French Republic, culminating in what has been called the greatest land deal in history.  The Louisiana Purchase was complete.  America had acquired about 828,000 square miles of land for about $15 million (roughly $233 million in today’s money, or about 42 cents per acre), nearly doubling the nation’s size.

The Louisiana Territory

Louisiana Territory was originally owned by the French.  La Salle took possession of it when he discovered the mouth of the Mississippi in 1691, and Louis XIV, King of France, named it after himself.  However, when the French lost the French and Indian War to the British, they were forced to give up all their possessions in North America.  Louisiana went to the Spanish.  The Americans were rather pleased with the arrangement, since Spain’s hold on the New World was a little bit shaky.  Many speculated that it would be quite easy to gradually enlarge the nation’s borders at Spain’s expense just by encroaching on a small piece of land at a time.  In the mean time, America and Spain settled a treaty of their own in 1795 quite favorable to the younger country, giving the United States the right to navigate the entire Mississippi River, and even deposit merchandise at New Orleans, if desired.

Things changed rather quickly after Napoleon came to power in 1799.  The ambitious emperor decided to restore France to its proper position of power in North America and worked out a new agreement with Spain — behind closed doors.  Louisiana Territory was restored to its former owners by secret treaty in 1800.  The secret did not last long, however. The American minister in France, Robert Livingston, caught wind of the proceedings and sent alarming messages back to his homeland, warning everyone that a French army would soon arrive to take immediate possession of New Orleans and destroy the Union.  The Spaniards neglected to execute the treaty until 1802, which gave the Americans plenty of time to work themselves into a fury.

Objections to the Louisiana Purchase

President Thomas Jefferson, meanwhile, wrote a letter to Livingston suggesting that France might be willing to give up a small part of the territory — say, New Orleans — if it would quell the commotion.  This proved to be a rather unpopular idea in America.  The Federalists objected to any kind of an entanglement with Napoleon.  Jefferson’s own party protested that there was nothing in the Constitution that gave the federal executive the power to purchase land in this manner.  Jefferson agreed that his proceedings were unconstitutional and had the potential to jeopardize state rights.  However, he desperately wanted to get the French out of the vicinity and to protect trade on the Mississippi River.  So he went ahead and sent James Monroe to Paris to help Livingston buy New Orleans, or at the very least secure American access to the port.

Napoleon and the Louisiana Purchase

By this time, Napoleon’s fortunes had changed, and not for the better as far as he was concerned.  A slave revolt in Haiti had interfered with his revenues at a time when he needed every penny he could spare to fight the British.  He had neither the troops nor the funds to bother with North America, so he decided that he might as well make the best of things.  When Livingston and Monroe began treating with Napoleon’s representative, Barbé Marbois, to their astonishment they were offered the entire Louisiana Territory.

The Louisiana Purchase: A Unit Study

Napoleon really had no right to sell Louisiana to the Americans.  He had promised the Spaniards in the secret treaty that he would never sell or alienate the territory to a third party, and Jefferson, Livingston, and Monroe appear to have been aware of this.  However, it was too good of an opportunity to pass up. The treaty was signed after only two weeks of negotiation. Livingston said afterward, “We have lived long, but this is the noblest work of our whole lives.”

America was suddenly pushed to worldwide importance, but it came at the price of friction with Spain.  The Spaniards, needless to say, were enraged, and insisted that their upstart neighbors had rights only to a narrow strip of land along the Mississippi River.  The United States, however, claimed that the Rio Grande was the border between the two rival countries.  Jefferson sent out three expeditions to examine the new territory and its borders — Lewis and Clark, Zebulon Pike, and a lesser-known Red River Expedition.  The charts and records kept by the various explorers eventually provided the basis for a treaty in 1819. America managed to hold onto most of the land it claimed.

Implications of the Louisiana Purchase

Some of the other implications of the Louisiana Purchase were not settled so quickly.  For instance, the purchase marked the beginning of Manifest Destiny — the idea that it was clearly ordained for America to stretch from the Atlantic to the Pacific — which took about half a century and countless pioneers to fulfill.  The question of whether or not to allow slavery in the territory arose almost immediately and insisted on rearing its ugly head repeatedly until the Civil War ended.  And finally, the Louisiana Purchase established some precedent for the elasticity of the elastic clause (Article 1, Section 8, Clause 18), which gives Congress the power to “make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof” — the proper interpretation of which hasn’t been settled yet, and perhaps never will.

Further Investigation

The Louisiana Purchase
Brief overview from Enchanted Learning.

The Louisiana Purchase
Background from the National Park Service.

Louisiana Purchase Legislative Timeline
Browse by year.

Transcription: Louisiana Purchase
Text of the original documents from the National Archives.


An Empire for Liberty
Interactive from PBS that includes many asides as it explains the Louisiana Purchase — a segment from A History of US series.

Animated Atlas of the United States
This free interactive shows the growth of the United States — and the enormous impact of the Louisiana Purchase.

Louisiana Purchase Map
Map activities.

Louisiana Purchase and Exploration Map Activity Instructions
More map activities.

Graphic Organizer
Use this printout from Glencoe to list the benefits of the Louisiana Purchase.

Find the Main Idea
One way to wrap up.

The Louisiana Purchase

The Louisiana Purchase by Gail Sakurai
Part of the Cornerstones of Freedom series, begins with La Salle claiming Louisiana for France and continues through the political maneuvers that allowed Jefferson to double the United States at an incredibly low cost.  Although slow at times, still a favorite series for providing detailed, foundational accounts.

The Louisiana Purchase by Binger Hermann
Commissioner of the General Land Office gives an 1898 synopsis.  Short and interesting read including history beginning in the late 1600s and many maps.

Unit Studies & Lesson Plans

Louisiana Purchase
Free lesson plan that provides background and includes comprehension, letter writing, and other activities.

Jefferson and the Louisiana Purchase
Quick lesson plan that provides summary, narrative, and discussion questions relating to Jefferson’s concerns about the constitutionality of the Louisiana. Purchase.

Free History Studies: Lewis & Clark

Free History Studies: Lewis & Clark
More Louisiana Purchase resources in our free history study.

Printables & Notebooking Pages

Color Map
Showing the Louisiana Territory.  Great for notebook!

Louisiana Purchase Map
Map to color for notebook from SurfNet Kids.

The Louisiana Purchase Notebooking Pages
Simple pages for copywork, narrations, or wrapping up.

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