One factor was the encouragement of the federal government. The federal government provided land grants along the right-of-way of major railroads. The railroads could then sell this land and make money not only from shipping but land sales as well.
Another thing that helped the growth of railroads was the rapid westward expansion of the United States after the Civil War. Millions of immigrants and poor whites from the South looked at the cheap land west of the Mississippi as a place to get a fresh start. Many immigrants also worked on creating railroads as track layers. As the Native American populations were placed on smaller reservations, more land was opened up to farming. These emigrants demanded supplies and access to markets which railroads provided. Railroads also developed monopolies over the shipping in many regions, thus allowing them to turn a great profit until they were regulated at both the state and national levels.
The final thing that allowed railroads to grow and...
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