Johnson County is the northeastern most county in Tennessee, sharing borders with Virginia and North Carolina. The county is situated entirely in the Blue Ridge Mountains and is made up of many small towns and communities situated over four mountains, three valleys and along one big lake. It is one of the highest counties in Tennessee, and it has a total area of 303 square miles, of which 298 square miles is land and 4.2 square miles is water.

Mountain City is the largest town in the county and serves as the county seat. The county is governed by a Board of Commissioners and a county mayor. There are (8) voting districts in the county represented by 15 Commissioners. The county is located within Tennessee’s 1st congressional district.

Johnson County was created in 1836 from parts of Carter County, where Elizabethton was the county seat. The residents of what is now Johnson County tried for years to get the county to move the seat to a more central location, because it was so difficult to travel to Elizabethton. Their formal petition was rejected by the county, so they petitioned the state legislature for the creation of a new county. The new county was named after Thomas Johnson, an early settler.

Mainly due to the remoteness of the county, the railroads did not reach Johnson County until the early 1900’s. The arrival of the railroad greatly helped the development of the timber and manganese mining industries.