The Nashville, Chattanooga & St. Louis Railway began as the Nashville & Chattanooga Railroad, chartered in Nashville, Tennessee, on December 11, 1845. Built to five-foot gauge, the Nashville, Chattanooga & St. Louis was the first railway to operate in Tennessee. In 1880, the Louisville & Nashville Railroad took a controlling interest through a hostile stock takeover. The railroads operated separately until merging in 1957.
The Selma, Rome and Dalton Railroad Company was created on August 6, 1866, by consolidating the Alabama and Tennessee River Rail Road Company, the Georgia and Alabama Rail Road Company, and the Dalton and Jacksonville Railroad Company. The Georgia General Assembly ratified the merger on December 13, 1866, and the Alabama Legislature on February 8, 1867. Following the Civil War, former Confederate General Joseph E. Johnston served as president of the Alabama and Tennessee River Rail Road Company and served from May 1866 to November 1867. The railroad company constructed 135 miles of track between Selma, Alabama, and Blue Mountain, Alabama, with an extension towards Dalton, Georgia. In 1870, the Selma, Rome and Dalton Railroad completed a 100.3-mile extension between Blue Mountain and Dalton, Georgia. Financial difficulties led to the railroad's foreclosure and sale. The Georgia section was sold to the Georgia Southern Railroad in 1874 and later acquired by the East Tennessee, Virginia and Georgia Railroad in 1880 and became part of the Southern Railway Company on July 7, 1894.