Tennessee County, North Carolina was a subdivision of the state of North Carolina in the Overmountain Region—which later became the state of Tennessee.
Tennessee County was organized in 1788 from a portion of Davidson County, North Carolina. Both were transferred, along with the state's five other western counties (the former Washington District), to Federal jurisdiction in 1790 and formed into the Southwest Territory. The county was divided into Montgomery and Robertson counties in 1796, when Tennessee became the nation's 16th state. The land area formerly included in Tennessee County now forms Humphreys, Montgomery, and Robertson counties and portions of Stewart, Dickson, Cheatham, and Houston counties.
References
Tennessee County, North Carolina Wikipedia(Text) CC BY-SA