The Middle Atlantic states, commonly shortened to Mid-Atlantic states, is a region of the United States generally located in the overlap between the Northeastern and Southeastern States. Its exact definition differs upon source, but the region usually includes New York, New Jersey, Pennsylvania, Delaware, Maryland, Washington, D.C., Virginia and West Virginia. When discussing climate, Connecticut is sometimes included in the region, since its climate is closer to that of the Middle Atlantic states than the rest of the New England states. The Mid-Atlantic has played an important role in the development of American culture, commerce, trade and industry; in the late 19th century, the Mid-Atlantic was called "the typically American" region by Frederick Jackson Turner.