Final answer:
The Alaskan purchase was negotiated with Russia in 1867 under the leadership of US Secretary of State, William Seward.
Step-by-step explanation:
The Alaskan purchase was negotiated with the country of Russia. This monumental purchase occurred in 1867 under the leadership of United States Secretary of State, William H. Seward. Known as Seward's Folly or Seward's Icebox, the acquisition added approximately 586,412 square miles of new territory to the United States.
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