Final answer:
William Seward purchased Alaska from Russia in 1867.
Step-by-step explanation:
William Seward purchased Alaska from Russia in 1867. Seward was the U.S. Secretary of State under President Andrew Johnson. The purchase of Alaska, also known as 'Seward's Folly' at the time, cost the United States $7.2 million and added over 586,000 square miles of land to the country.
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