Cowan, Tennessee, was named in honor of Major John Cowan, an early pioneer settler. Major William Russell first settled here in 1800, and his home served as the first courthouse from 1807 to 1814. From 1848 to 1854, the N &C Railroad constructed the world's longest tunnel and steepest grade railroad. In 1855, a nine-mile spur line to Sewanee Mountain was completed by the Sewanee Mining Company. During 1863 and 1864, Confederate and Federal armies camped in Cowan, and the failure of Confederate forces to destroy the tunnel provided General Sherman with a direct line of supply for his march through Georgia.