Russia sold Alaska to the United States in the 1867 deal remembered as part of America's national expansion.
The United States and Russia signed the Alaska purchase treaty on March 30, 1867. The United States paid $7.2 million, equivalent to about two cents per acre, and formally took possession on October 18, 1867. Secretary of State William H. Seward negotiated the agreement for the United States.
The purchase was widely mocked by some Americans as “Seward's Folly” or “Seward's Icebox,” but Alaska later proved valuable for its natural resources and strategic position. Russia wanted to reduce the risk of losing the remote territory to Britain in a future conflict and needed revenue after the Crimean War. Alaska became a U.S. territory in 1912 and the 49th state in 1959.