Revenue: $4.9 billion
Italy has four major mafia gangs that make a reported $33 billion dollars a year. Camorra happens to be the most successful of these four gangs, bringing in almost $5 billion a year. The Naples-based group makes its money from sexual exploitation, firearms trafficking, drugs, counterfeiting, and gambling. The gang originated in the 19th century as a prison gang and then got its rise during the political struggle in Italy during the 1800s by offering protection to citizens.