Davidson County is a county in the U.S. state of Tennessee. It is located in the heart of Middle Tennessee. As of the 2020 census, the population was 715,884, making it the 2nd most populous county in Tennessee. Its county seat is Nashville, the state capital and most populous city. Since 1963, the city of Nashville and Davidson County have had a consolidated government called the "Metropolitan Government of Nashville and Davidson County", commonly referred to as "Metro Nashville" or "Metro".