Which state joined the U.S. most recent?

Hawaii is the 50th and most recent state to have joined the United States of America, having received statehood on August 21, 1959. In March 1959, Congress passed the Hawaii Admission Act, which U.S. President Dwight D. Eisenhower signed into law. On June 27, 1959, a referendum asked residents of Hawaii to vote on the statehood bill; 94.3% voted in favor of statehood and only 5.7% opposed it.