The Chicago and Alton Railroad began service in 1847 in Illinois as the Alton and Sangamon Railroad and later linked Alton to Springfield and Joliet. However, financial reverses forced the Company through several bankruptcies and name changes until about 1855 when the Road was reorganized as the Chicago and Alton. The heyday of the Chicago and Alton Railway occurred after the Civil War when it operated nearly 1000 miles of track.

By 1879 the Line was complete: beginning in Chicago, it bridged the Mississippi River at Louisiana, Missouri, extended through the town of Mexico to bridge the Missouri River at Glasgow and arrived at Kansas City, its western terminus, all on its own rails. Around the turn of the century, the E.H. Harriman Syndicate bought the Line, watered its stock, and shifted its assets first to the Union Pacific, then the Rock Island, and finally the Clover Leaf. After the Company's third receivership, it was sold to the Baltimore and Ohio Railroad in 1929 and renamed the Alton Railroad.

In 1942, the Line was again sold to the Isaac Tigrett System where it helped form the nation's second Mid-Continent trunk line between Chicago and the Gulf under the Gulf, Mobile and Ohio Railroad name. Finally, in 1972, the Company merged with the Illinois Central to form the current Illinois Central Gulf System.