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Jefferson and the Louisiana Purchase


Thomas Jefferson had always feared the costs of loose construction of the powers delegated to the national government in the Constitution, and the Constitution was silent about acquiring lands from other countries. Jefferson urged bringing the issue to the people to approve with a constitutional amendment, but Congress disregarded his draft amendments. The Senate ratified the Louisiana Purchase Treaty in October of 1803. While Jefferson did his best to follow what he believed was proper constitutional procedure, not enough of his contemporaries agreed with him and he eventually assented.


France had given up all of its territory in North America by the end of the French and Indian War (1763). But Napoleon had plans to re-establish the French empire in North America. In 1801, America learned that Spain had agreed to return Louisiana to France. Jefferson had always looked upon France as a friend in the world, but he knew this was a potential crisis. The new nation depended on New Orleans for its economic survival.

In early 1803, Jefferson appointed James Monroe as a special envoy to France. Monroe and Minister to France Robert Livingston would try to buy land east of the Mississippi or in New Orleans itself, or, if all else failed, to secure U.S. access to the river. Jefferson authorized them to negotiate up to $10 million. Monroe and Livingston learned that Napoleon had given up his desire to recreate an empire in North America. France offered the U.S. the entire Louisiana territory—more than 800,000 acres from Louisiana to the Rockies and beyond—for $15 million.  The two American ministers seized the opportunity, going beyond their mandate. They negotiated a purchase treaty and returned to the U.S. in time for an announcement to be made on July 4, 1803.

The Louisiana Purchase Treaty would not be final until it was ratified by the Senate, funded by the House of Representatives, and signed by the President. While the incorporation of these new lands into the United States was a momentous opportunity, Jefferson had reservations about its constitutionality.  Jefferson had always stated his strong belief that the federal government’s powers should be interpreted strictly. Article IV of the Constitution said new states could be added, but made no provision for taking on foreign territories, Jefferson argued that a constitutional amendment was needed. He wrote in 1803, “The General Government has no powers but such as the Constitution gives it… it has not given it power of holding foreign territory, and still less of incorporating it into the Union. An amendment of the Constitution seems necessary for this.”

Jefferson drafted an amendment that would authorize the purchase of Louisiana retroactively. But Jefferson’s cabinet members argued against the need for an amendment, and Congress disregarded his draft. The Senate ratified the treaty in October of 1803.

Jefferson may have had to compromise his most sacredly-held principles for the Louisiana Purchase to go forward. But he later described the Purchase as a “great achievement.” He wrote in 1810, “It is incumbent on those who accept great charges to risk themselves on great occasions.” President Thomas Jefferson doubled the size of the United States and set a precedent for the acquisition of new lands through means other than war and conquest.  France turned New Orleans over to the United States on December 20, 1803.


  1. What instructions did President Jefferson give to Monroe and Livingston?
  2. What happened when the two men began negotiations?
  3. Why did Jefferson have concerns about the constitutionality of the Louisiana Purchase?
  4. Should Jefferson have continued to insist that a retroactive amendment was needed? Why or why not?