What US state became the 50th state in 1959?

The US state that became the 50th state in 1959 was Hawaii.

Hawaii entered the Union on August 21, 1959, after Congress passed the Hawaii Admission Act and President Dwight D. Eisenhower signed it on March 18. The act ended Hawaii’s territorial status and established the State of Hawaii as the nation’s 50th state. A June 27 plebiscite on statehood produced an overwhelming vote in favor.

Hawaii’s admission followed Alaska’s, which became the 49th state on January 3, 1959. That sequence is the source of a common mix-up: Alaska was admitted earlier in the same year, but Hawaii was the final state to join. Hawaii had been an organized US territory since 1900, following the islands’ annexation by the United States in 1898. The Admission Act also excluded several Pacific territories, including Palmyra Atoll, from the new state.