By the time Thomas Jefferson became the third U.S. president in 1801, the United States stretched from the Atlantic Ocean to the Mississippi River. Jefferson knew that gaining access to the river and the Gulf of Mexico would greatly strengthen the young nation. However, that land was controlled by France, and  French leader Napoleon Bonaparte wasn’t interested in making a land deal with the United States. Jefferson wouldn’t give up, so he sent in James Monroe to try again, and the Louisiana Purchase was born. Monroe secured the largest land deal in the nation’s history and almost doubled the size of the country: the entire Louisiana Territory – 827,000 square miles – for $15 million.

Napoleon’s Plan, Thwarted

Napoleon wanted a French Empire across North America. He planned to send 25,000 soldiers and 63 ships to New Orleans, to occupy the city. But it wasn’t meant to be. A slave revolt in the Caribbean and an outbreak of yellow fever defeated his plan. In the end, Napoleon lost over 60,000 troops and had no hope of establishing a strong presence in Louisiana. By the time Jefferson sent Monroe to negotiate a land deal for New Orleans, Napoleon just wanted out of the colony and needed money for a war with England.

Westward Expansion and the Anti-Federalist Dilemma

President Jefferson had several reasons for wanting to make the land deal, but the main reason was national security. He had hoped only for the port of New Orleans. When Monroe returned with the news that Napoleon wanted to sell all of Louisiana for $15 million, Jefferson was faced with a dilemma.

The benefits of the Louisiana Purchase were obvious, but Jefferson was strongly anti-federalist and didn’t believe that the government should have any more power than exactly what the Constitution said – and the Constitution didn’t say he could make that purchase. Jefferson worried that if he waited for a change to the Constitution, the deal would fall through and there would be no way to avoid war with France. So he compromised. With the support of the American people, Jefferson agreed to the purchase.

Manifest Destiny, From Sea to Shining Sea

The Louisiana Purchase, which was made in 1803, went down in history as the greatest accomplishment in Jefferson’s presidency. It nearly doubled the size of the United States and led to the idea that the nation had a “Manifest Destiny” to reach from the Atlantic to the Pacific. The Louisiana Purchase changed the way other nations dealt with the United States and played major roles in both the War of 1812 and the Civil War. Indeed, without the land that eventually became 15 new states, the Civil War might never have happened.