The Alaska Purchase (Russian:Продажа Аляски, tr.Prodazha Alyaski) was the United States' acquisition of Alaska from the Russian Empire in 1867 by a treaty ratified by the United States Senate.

Russia wanted to sell its Alaskan territory, fearing that it might be seized if war broke out with Britain. Russia's primary activities in the territory had been fur trade and missionary work among the Native Alaskans. The land added 586,412 square miles (1,518,800 km) of new territory to the United States.