officially the Commonwealth of Kentucky, is a state located in the Southern United States. Although styled as the “State of Kentucky” in the law creating it,[5] (because in Kentucky's first constitution, the term “state” was used), Kentucky is one of four U.S. states constituted as a commonwealth (the others being Virginia, Pennsylvania, and Massachusetts). Originally a part of Virginia, in 1792 Kentucky split from it and became the 15th state to join the Union. Kentucky is the 37th most extensive and the 26th most populous of the 50 United States.