Kentucky is admitted as the 15th state of the United States.

Kentucky, officially the Commonwealth of Kentucky, is a landlocked state in the Southeastern region of the United States. It borders Illinois, Indiana, and Ohio to the north, West Virginia to the northeast, Virginia to the east, Tennessee to the south, and Missouri to the west. Its northern border is defined by the Ohio River. Its capital is Frankfort and its most populous city is Louisville. As of 2024, the state's population was approximately 4.6 million.

Admission to the Union is provided by the Admissions Clause of the United States Constitution in Article IV, Section 3, Clause 1, which authorizes the United States Congress to admit new states into the Union beyond the thirteen states that already existed when the Constitution came into effect. The Constitution went into effect on June 21, 1788, in the nine states that had ratified it, and the U.S. federal government began operations under it on March 4, 1789, when it was in effect in 11 out of the 13 states. Since then, 37 states have been admitted into the Union. Each new state has been admitted on an equal footing with those already in existence.

In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sovereignty with the federal government. Due to this shared sovereignty, Americans are citizens both of the federal republic and of the state in which they reside. State citizenship and residency are flexible, and no government approval is required to move between states, except for persons restricted by certain types of court orders.