The Mafia was started in Sicily during medieval times to protect the estates when the landlords were not there. By the 1800's the Mafia had become criminal and used violence throughout Sicily. The members were sworn by a strict ethical code called omerta. That was a group of rules and if you broke one you died. The Mafia became so strong that they became politicians and were able to influence police forces and gain access to weapons. The Italian government under Benito Mussolini tried to control the Mafia but it came out strong again after World War II. Because of Mussolini being so strict members of the Mafia moved to the United States where they then led many criminal activities especially during Prohibition. By the 1930's it moved into other illegal activities.