Here is a list of different types of organised crime across the globe. These can be enemies in many different ways. Perhaps they are infringing on the mafia's territory, or even vice versa. The White Wolf book Destiny's Price has some information on all types of organised crime.
Hong Kong/China — Triads: seen more often as pirates than gangsters, the Triads are known for using the seas to hi-jack cargo and then sell it off. A good source of rpg info is White Wolf's Kindred of the East supplement Killing Streets. (Book/Game: the Triad Sourcebook for Hong Kong Action Theatre, Shadowrun or Cyberpunk and Killing Streets, Movie: Black Rain)
America (California) — Hell's Angels: more than just a motorcycle gang! They have a history of drug dealing and other crimes. The group ran on intimidation for a very long time and the fear that they generated in the general population, however, the police did eventually start to crack down on their operations. (Book/Game: there are a few Fudge supplements covering the motorcycle aspects, such as Route 666 and Fudge: Full Throttle, Movie: Hell's Angels)
Jamaica — Yardies: expanding drug marketeers that have taken their wars from the small island to the mean streets of England. The last few years of upheaval in this small country have been wars over the drug trade of rival factions. (Book/Game: Delta Green: Countdown, Movie: )
Colombia — Medellin Cartel: one of the largest drug syndicates in the world with few competitors that can match it for power. This organisation has thrived in countries where the legal system can not adapt fast enough to trap the dealers. However, drug cartels do go through cycles and it is highly unlikely that one cartel with stay in power for very long before they are killed or overthrown by a competitor. Known for ruthlessness and brutality but haven't been able to establish themselves in North America as mainstays against the mafia and the hoods in regards to dealing drugs. (Book/Game: Destiny's Price , Movie: Scarface [Al Pacino version])
Japan — Yakuza: very similar to the Sicilian mafia in origin and organisation. They saw themselves as 'Robin Hood' type figures, but soon became a self-driving force. The Yakuza control a lot of the drug trafficking in the Asia-Pacific area. A good source of rpg info is White Wolf's Kindred of the East supplement Killing Streets. (Book/Game: Shadowrun or Cyberpunk and Killing Streets, Movie: Brother)
Russia — Chechens: a huge organisation founded on fraud. The country's technology in banking and economics is so far behind that these organisations have been able to come away with huge fortunes without any risk of being caught. Smuggling, money laundering and drug trafficking thrived under the Communist system, which basically had no laws to stop racketeering. There are various other syndicates that are present in the Eastern Bloc. (Book/Game: Destiny's Price , Movie: )
UK — Irish and English Mobs: a formidable power and the Irish Mob was a strong force in America before prohibition. Involved in a lot of underground activities, but does not have the same strong organisation of these other syndicates. (Book/Game: Steal (free game) and Gangbusters, Movies: Lock, Stock & Two Smoking Barrels and Snatch)
The Jewish Mob — the leaders of organised crime in the US for many years. The controlled almost all the banks and money before prohibition. Their only major competitors were the Irish. (Book/Game: Gangbusters, Movies: Once Upon A Time In America, Lansky)
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