Hawaii became the 50th and most recent U.S. state in 1959.
President Dwight D. Eisenhower signed the Hawaii Admission Act, and Hawaii joined the Union on August 21, 1959. The admission followed a referendum in which Hawaiian voters approved statehood by a large majority.
Hawaii had been a U.S. territory since 1898, after the United States annexed the islands. Before annexation, the Kingdom of Hawaii was overthrown in 1893 by a group that included American and European residents; the United States later acknowledged the role of its representatives in the overthrow.
Hawaii is the only U.S. state made up entirely of islands and the only state located in Polynesia. Its statehood completed the current map of the United States. Alaska entered the Union earlier in 1959, making Hawaii the 50th state rather than the 49th.