The Louisiana Southern Railway Company (LS) was a railroad in southern Louisiana, chartered in 1897 as successor to several short lines which had operated along the Mississippi River, including Mississippi, Terre aux Boeuf, and Lake; New Orleans and Gulf; and New Orleans and Southern, that eventually became part of the Southern Railway system.
The Railway was originally owned jointly by Franklin (Frank) Emery Prewett (1872-1936) and his half-brother, Granville Prewett (1896-1973). both of Baton Rouge, Louisiana. Frank was the son of Vernal Franklin Prewett (1841-1911), of West Virginia, then Tennessee, and his first wife, Susan C. Ross (c. 1850-1878). Granville was the son of Vernal Franklin Prewett and, apparently, his second spouse, Emma Lucy Ross. In 1907, the elder Prewett then married Ardelia (Della) Bowers, later Gooch (1868-1916).
The LS Railway served the truck farms, or large-scale market gardens, of the Mississippi Delta throughout the Great Depression.
In 1952, Southern bought the 15-mile line, running along the Mississippi River from New Orleans to Braithwaite.