15 vintage photos of the American Mafia that show their lasting legacy

• The American Mafia started in the 1920s when the mob bosses ran the bootlegging industry during Prohibition. 
• From there, the Mafia became a national organization dealing with prostitution, gambling, and bribery.
• The mob is most well known for its brutal murders and beatings.  
• Al Capone was one of the most famous mobsters who brutally murdered his rivals.
• Visit INSIDER's homepage for more stories.

While many associate the Mafia with HBO's hit show "The Sopranos," the mob is a very real and ruthless organization with a bloody history. 

Headquartered in New York, the American Mafia got its start in the '20s and hit its peak during the '40s and '50s, eventually reaching a downfall in the '80s. Throughout that time, the mobsters ran a brutal, bloody, and illegal operation, mostly under the radar.  

Keep scrolling to learn more about the Mafia's gruesome history in the US. 

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The Mafia can be traced back to the 1800s on the Italian island of Sicily.

Before being unified with Italy, Sicily was subject to a number of foreign invasions by the French, Spanish, and Arabs. The Sicilians rallied together in small groups to protect themselves and their families from the ongoing invaders. These groups acted as gangs, extorting money from landowners. Eventually, the groups infiltrated the government and influenced the economy. 

To strengthen their power, these Sicilian gangs — now known as the Mafia — held induction ceremonies and relied on important codes of conduct.

The most important aspect of the Mafia at this time was known as the omerta, which said members should never turn to the police or the government for justice and that they should never cooperate with such agencies. In other words, it was a code of silence. 

In the early 1900s, Italian immigrants flocked to the United States.

In New York, there were 500,000 Italian immigrants by 1910. Although the vast majority of these immigrants were law-abiding citizens, some criminals did cross over to the States.