The ban on alcoholic drinks in the United States led to a surge in the demand for illegal alcohol.
Millions of Americans were avid drinkers, but the ban took away a part of what many saw as their culture and their right.
Local criminals and gangster took up the responsibility of making money by selling illegal alcohol. A steady supply and even better demand, quickly made these criminals very rich.
This, in turn, led to the development of organized criminal gangs who had a lot of influence with politicians, business people and even with the ordinary folk of their towns.