How does vanderbilt acquire nearly half of all the railroads across america

In the 1860s, Cornelius Vanderbilt started with the railroad business gaining control of some railway lines operating between Chicago and New York.

The main success of Vanderbilt in the railroad industry was the creation of a coherent system expanding to several states, lowering costs, improving efficiency and cutting times to travel.

He acquired almost half of all the railroads in America due to the franchise of the state to build up a kingdom in the US, taking the monopoly of the business.