Which state was once an independent kingdom?

Hawaii is the only U.S. state that was once a kingdom with its own monarchy. From 1810 to 1893, Hawaii was an independent kingdom, ruled by King Kame-hameha I and his successors, including David Kalakaua, the last king of Hawaii. It was formally annexed by the United States in 1898, became a territory in 1900, and was admitted to the Union as a state in 1959. The state of Hawaii is made up of eight main islands Niihau, Kauai, Oahu, Maui, Molokai, Lanai, Kahoolawe, and the Big Island of Hawaii and is America’s 50th state.