Which purchase from France in 1803 greatly expanded the territory of the United States?

The Louisiana Purchase from France in 1803 greatly expanded the territory of the United States.

The United States agreed to purchase the Louisiana territory for $15 million. The treaty was signed in Paris on April 30, 1803, and the transfer was completed later that year. The acquisition covered about 828,000 square miles, although its exact boundaries were not immediately clear.

The territory stretched west from the Mississippi River toward the Rocky Mountains and extended from the Gulf of Mexico northward. It gave the United States control of New Orleans and the Mississippi River system, which were vital for trade and settlement. President Thomas Jefferson supported the deal even though the Constitution did not explicitly describe a power to acquire foreign territory.

The purchase roughly doubled the size of the United States. It did not immediately settle the status of Indigenous nations or resolve conflicts over slavery’s expansion. The later exploration of the region by the Lewis and Clark Expedition helped Americans map and publicize parts of the new territory, but the expedition did not itself create the purchase.