Fayetteville is the county seat and the largest city in Lincoln County, Tennessee, United States. The city's population was 7,095 at the 20…Fayetteville is the county seat and the largest city in Lincoln County, Tennessee, United States. The city's population was 7,095 at the 2020 census. Fayetteville is the largest city in Lincoln County. The city was established in 1809 by an Act of the Tennessee General Assembly. The act became effective on January 1, 1810.