Which two countries were involved in the Louisiana Purchase?

The Louisiana Purchase involved the United States and France. In 1803, the United States bought the Louisiana Territory from Napoleon Bonaparte's French government for $15 million, dramatically expanding the young republic.

President Thomas Jefferson had initially sought access to New Orleans and the Mississippi River, which were vital for transporting agricultural goods from the American interior. France unexpectedly offered the entire territory after Napoleon abandoned plans to rebuild a French empire in North America. The agreement was signed in Paris on April 30, 1803, and formally announced in the United States on July 4.

The purchase covered roughly 828,000 square miles and nearly doubled the country's size, although much of the land was inhabited and governed by Native nations. Spain had controlled Louisiana before France regained it, so Spain is sometimes mentioned in discussions of the territory's earlier history. However, the purchase itself was a transaction between France and the United States.