Southern Pacific was founded as a land holding company in 1865, forming part of the Central Pacific Railroad empire. By 1900, SP had grown into a major railroad system which incorporated many smaller companies, such as the Texas and New Orleans Railroad and Morgan’s Louisiana and Texas Railroad. The Southern Pacific had noticeable social impact along its route; some towns prospered because of it and it founded a number of important hospitals in, among other places, San Francisco and Tucson. The takeover of Southern Pacific by Rio Grande Industries, along with the addition of the SPCSL route from Chicago to St. Louis, swelled the combined D&RGW/ SP/SSW system. While the Cotton Belt is the most famous of Southern Pacific’s subsidiaries, SP owned many others like the Northwestern Pacific, Southern Pacific Railroad Company of Mexico, and a variety of narrow gauge routes. The Southern Pacific subsequently was taken over by the Union Pacific Railroad in 1996 following years of financial problems