In the time after the Civil War, railroads had a tremendous impact on American society and business. They helped the country industrialize and created a situation in which the US became one big market instead of a number of smaller markets. By doing this, the railroads also helped to cause an increase in the size of American businesses. All of these things had major impacts on both business and society.
After the Civil War, the American railroad system started to boom. As this happened, the country industrialized. Railroads created a huge demand for steel, thus bringing about the first burst of industrialization in this time period. The railroads created a huge national market. They did so by tying together all of the various parts of the nation. Now, a firm in one part of the country could sell goods to people in other parts of the country without too much trouble. This helped lead to the creation of huge companies of a size that had never been seen before.
These things changed American business and society. They made America into a country of big businesses that needed to be run as bureaucracies. They helped to create a situation where many Americans moved into the middle class. They helped to make it so that these middle class Americans could buy consumer goods regardless of where in the country they lived. In these ways, the railroads changed American business and American society.