<human>:  Why is the state of Alaska listed twice in the List of states of the United States?
<bot>: Alaska was admitted to the Union as the 49th state in 1959. It was the last state to be admitted. It was originally named the Territory of Alaska, but it was renamed after the Alaska Purchase. Alaska was originally part of the Russian Empire, and then the Russian SFSR, the Soviet Union, and finally the Russian Federation. Alaska is the largest state by area and the least densely populated.