The United States has been home to some of the most notorious criminal gangs ever. So here, in a deep dive into the criminal underworld, we’ll go back as far back as the 17th century to guide you through some of the worst gangs in American history…

Chicago Outfit

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Formed in the 1900s, The Chicago Outfit was one branch of the ‘five families’, the most influential Mafia families in the United States. Before prohibition, their focus was on gambling, smuggling and prostitution until the infamous Al Capone took over in the 1920s and shifted the direction of their business to the alcohol racket, strengthening the gang’s power throughout Chicago and beyond.

Whilst Capone was in charge, he was responsible for over 200 deaths, including the murder of seven rival gang members in the famous St Valentine’s Day Massacre in 1929, although he was never charged. Capone, public enemy no.1 and known to his peers as ‘The Big Fellow’, was finally taken down and sentenced to 11 years in prison for tax fraud, not murder.

Hells Angels

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Formed in California in 1948 after merging several outlaw motorcycle groups, the Hells Angels Motorcycle Club (recognizable from its famous winged skull emblem) has a notorious history throughout the United States and beyond.

Recognized by the State Department as a “known criminal organization,” they participate in numerous crimes across the US, including gunrunning, loan sharking, kidnapping, robbery, theft, and drug trafficking. HAMC have repeatedly refuted these allegations and claim to be a ‘group of motorcyle enthusiasts’, whose members merely appreciate and ride Harley-Davidson style motorcycles.

With membership in the tens of thousands and various chapters based in 49 countries, HAMC has been involved in numerous court cases all over the world. The gang assert that any crimes committed are the responsibility of the members who carry them out, not the group as a whole. Despite this, they earn up to $1 billion a year in the narcotics trade according to the FBI.

Ku Klux Klan

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Beginning in the mid-1800s, infamous white-cloaked white supremacist group the Ku Klux Klan (KKK) operated a reign of terror over the United States unlike any other. Membership grew in the late 19th century and, during the civil rights era, the name of the gang became synonymous with racist, pro-white sentiment.

The far-right gang were the subject of DW Griffith’s celebrated but controversial 1915 film The Birth of a Nation, which mythologized the founding of the initial Klan and depicted them as a harmless, benevolent group. Consisting of civilian members who hid their identities, known as ‘Knights’, the KKK was subsequently responsible for countless crimes against ethnic minorities, including the destruction of property, terrorism and murder.

Since its multi-million membership peak in the 1920s, KKK numbers have been dwindling. Thankfully, despite a small but vocal membership, its presence in the United States today seems to be lessening.

Latin Kings

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After emerging in Chicago in the 1950s as a Puerto Rican political movement, the Latin Kings now operate in 31 states with over 30,000 members in different groups, or ‘tribes’, around the country. Members, organized in state, regional and national sects, also include the Latin Queens, a group made up entirely of women.

In Chicago, the city with the largest portion of Latin Kings members, the number exceeds 25,000 and constitutes one of the largest Hispanic street gangs in the entire country. A four month investigation by the New York Police Department (NYPD) led to the arrest of twenty gang members, charged with multiple crimes, including the murder of at least seven of their own.

The gang has considerable stakes in the US money laundering and narcotics trades and loyalty is vital. Members suspected of betraying this trust have been known to be killed, or, in King-Speak, TOS (terminated on sight).


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Reaching as far back as the 1600s, the Yakuza, a Japanese-born crime syndicate, are the oldest established group on this list. The group also holds special notoriety in the history of gangs operating in America. Currently formed of three prominent families and over 12,000 members, the gang operates numerous illegal gambling parlours and brothels.

Their notorious practices include ‘irezumi’ (extensive tattooing all over the body) and ‘yubitsume’ (amputation of the little finger), which occurs when a member has committed a trangression and must atone for his sins against their leader, the ‘Oyabun’ (head of the family).

In addition, the Yakuza has a significant stake in the trade of methamphetamine in the US, from which it exports guns back to Japan, where 33% of handguns seized originate from America and, presumably, the Yakuza.



Allies of the Japanese Yakuza, the Chinese Triads originated in Asia but have operated in America for decades. Originally a branch of the secret Hung Society formed to overthrow the Qing dynasty in the 17th century, the Triads have since been present throughout Europe and the US.

Triads organize themselves hierarchically using a numerical code that is based on an ancient Chinese divination scripture, the ‘I Ching’, and are headed by a member known as the ‘Dragon Master’ whose associated number is 489.

Central to the global heroin trade, their extensive operations also include fraud, extortion and counterfeiting goods such as handbags, clothes and DVDs. Although an ancient group, the Triads are still very much active in America, Europe, Asia and beyond.

La Cosa Nostra

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The American arm of the Sicilian Mafia, La Cosa Nostra began operating in the US in the 20th century after large-scale immigration from Sicily opened up myriad opportunities for them across the globe.

The gang, founded in Italy in the 18th century and linked together by blood and conspiracy, expanded across the world into the US, UK, Australia, Canada and South America, where they still operate, although on a somewhat smaller scale, today.

Described as an “industry of violence” by Italian publicist Leopoldo Franchetti, the gangs, or ‘families’, principally operate as settlers of disputes in local matters and abide by ‘commandments’ set by the gang and the ‘Omerta’ (code of silence), a common rule amongst the mafia groups in America, rules upheld by the threat of punishment and death.

James-Younger Gang

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A gang of notable 19th century outlaws and highwaymen led by Jesse James and Cole Younger, the James-Younger gang was amongst the most famous post-civil war gangs that operated mainly on the American frontier, popularly known as the Wild West.

The James-Younger gang worked successfully for almost two decades, amassing wealth through bank and highway robbery. They also operated in other fields of business, including; prostitution, gambling and the moonshine liquor trade.

Still, despite initial success and a growing reputation, their reign ended in 1876 when their attempt to rob the Northfield First National Bank failed, leading to Cole Younger being captured and the gang dissolving. Jesse James, co-founder of the group, was later shot in the back and assassinated after attempting to establish a new gang.

The Bloods

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The Bloods, an African-American gang founded in the 1970s in Los Angeles, are among the most notorious American-made criminal organizations. Widely known for their violent clashes with rival gang The Crips, The Bloods members are identifiable for wearing red colours and displaying a complex and recognizable hand sign that reads ‘BLOOD’.

Composed of different ‘sets’ and with their power bolstered by allies such as the Hispanic gang Latin Kings, the Bloods have continued to exert their influence using ruthless displays of public violence across 33 US states and Canada.

Membership is in the region of 15,000, and members call themselves ‘dawgs’, CKs (Crip-Killers), or MOBs (Members of Blood). Regions of the US that have a large Blood presence can often be spotted by the presence of graffiti pertaining to the gang, through which the gang mark their territory.

Mara Salvatrucha


Mara Salvatrucha (MS-13) are widely accepted to be among the most violent gangs operating in the United States today. Members are composed largely of Central Americans and Salvadorans, as well as other people of Hispanic heritage. Aspiring members are subjected to a violent 13-second ‘beat in’, wherein they are beaten for 13 seconds by other members of the gang.

They are especially known for their unrelenting violence against women and children, often used by the gang to publicly assert their dominance and demonstrate their power within certain territories. Since the gang’s inception in California in the mid-1970s, membership has grown from delinquent heavy-metal fans into an openly violent international operation.

The district attorney for Nassau, New York, stating in 2018, “we have uncovered a structured network of MS-13 operations in New Jersey, Maryland, Virginia, Texas, from within a Mississippi prison cell, and in countries around the globe including Mexico, Colombia, Korea, France, Australia, Peru, Egypt, Ecuador and Cuba.”