On what date did Hawaii become the 50th U.S. state?

Hawaii became the 50th U.S. state on August 21, 1959.

President Dwight D. Eisenhower signed the Hawaii Admission Act earlier that year, and Hawaii was formally admitted to the Union on August 21. William F. Quinn became the state’s first governor. The admission followed a June 1959 referendum in which Hawaii voters approved statehood by a large majority.

Hawaii was the final state admitted to the United States, following Alaska’s admission as the 49th state on January 3, 1959. The order is sometimes reversed because Alaska’s statehood occurred earlier in the same year. Hawaii’s admission completed the current 50-state Union represented in the America250 era.