Knox County is a county in the U.S. state of Tennessee. As of the 2010 census, the population is 432,226. Its county seat and largest city is Knoxville. The county is at the geographical center of the Great Valley of East Tennessee. Near the heart of the county is the origin of the Tennessee River at the union of the Holston and French Broad Rivers.
Knox County was created on June 11, 1792 by Governor William Blount from parts of Greene and Hawkins counties, and has the distinction of being one of only eight counties created during territorial administration. It is one of nine United States counties named for American Revolutionary War general and first United States Secretary of War Henry Knox. Parts of Knox County later became Blount (1795), Anderson (1801), Roane (1801), and Union (1850) counties