On October 18, 1867, the U.S. formally takes possession of Alaskaafter purchasing the territory from Russia for $7.2 million, or less than two cents an acre. Indigenous peoples settled the unforgiving territory thousands of years earlier. The Alaska purchase comprised 586,412 square miles, about twice the size of Texas, and was championed by William Henry Seward, the enthusiastically expansionist secretary of state under President Andrew Johnson.