In 1867 the United States purchased the Alaska territory from Russia.
The purchase was negotiated by Secretary of State William Henry Seward.
The Russian government had it’s own reasons for wanting to sell Alaska, but at the time it was perceived as useless territory by many in the US.
Alaska was referred to derisively as “Johnson’s Polar Bear Garden” and more famously “Seward’s Folly.” William Seward was vindicated after his death, when gold was discovered in Alaska, and later oil.