In 1803, the Louisiana Purchase by the United States for $15 million increased the amount of territory the country owned by 828,000 square miles, doubling its size. The newly acquired land stretched from the Mississippi River in the east to the Rocky Mountains in the west, and from the Gulf of Mexico in the south to the Canadian border in the north. The land was bought from France and is made up of, a part of or all, 15 states including Arkansas, Iowa, Kansas and Louisiana.
France had gained control of the territory from 1699 but ceded it to Spain in 1762. Napoleon had negotiated French ownership again by 1800. The country was forced to sell the territory to America, because of the threat of war with the United Kingdom and a slave revolt in their territory of Saint-Domingue. The Americans had initially been interested in buying New Orleans, and James Monroe and Robert Livingston traveled to Paris to negotiate the purchase. They were offered a much larger area and were quick to accept. The United States agreed to pay $11,250,000, as well as pardon France a debt totaling $3,750,000. The government gave the French $3 million in gold as a down payment and issued bonds for the balance due. By the end of the year France had transferred the region’s authority to the United States.
This was the largest territorial gain by America, and one of the most notable achievements of Thomas Jefferson’s presidential career. Exploration and expansion of the new area began almost immediately, and a territorial government was established in 1804. Jefferson quickly commissioned the Lewis and Clark Expedition to explore the newly acquired lands, because the western boundary was still being contested. The maps and journals of these explorers, as well as those of two other expeditions, helped to define the boundaries.
The territory proved to be more difficult to govern than it had been to acquire. There was a large population of slaves, as well as free blacks, especially in Louisiana and Arkansas, whereas Missouri had many slaveholders. These slaveholders wanted laws to be established to allow them to take their slaves to the area, as well as decrease the threat of future rebellion. The territory was divided into smaller areas to be governed, and many of them passed similar slavery laws to those in the southern states. On April 30, 1812, the first state that had arisen because of the acquisition, Louisiana, became a part of the Union. This was exactly nine years after the purchase agreement had been made.