In The Mob: 200 Years of Organized Crime in New York, not an academic monograph but a popular history of organized crime in the Big Apple, Virgil Peterson begins with the roots of Tammany Hall in the late 18th century (even crediting Aaron Burr with transforming Tammany from a social to political club), before tracing the origins of the Five Points and Bowery gangs. Throughout its history, organized crime in New York as traced by Peterson (and elsewhere) was multi-ethnic, reflecting the make-up of the city.

As Italian immigration increased in the late 19th century, crimes perpetrated by and on Italians increased as well. Peterson writes of "armed gunmen" roaming the streets of Italian neighborhoods, and Black Hand extortionists preying on Italian and Jewish immigrants (108). It's worth saying that the Black Hand was not an organization, but merely a method of extortion in which criminals would threaten shopkeepers, etc with violence unless they paid protection money, signing the demand note with a black hand. Sometimes, the shopkeepers fought back, and there was no reprisal from a bigger organization. Policeman Joseph Petrosino was named to head a squad tasked with specifically investigating Italian-American crime, which Police Commissioner William McAdoo insisted was a local phenomenon, and not linked to a larger criminal conspiracy "such as the Mafia or Black Hand (109)." In 1909, however, Petrosino was gunned down while investigating Italian criminals who had come to America while in Sicily, jump-starting talk of a Sicilian-based criminal organization.

Through Prohibition, American organized crime remained multi-ethnic and local, with "rackeeters" and "hoodlums" (as they were variously known) coming from mostly Irish, Italian, Jewish, African-American, and WASP backgrounds. The "Big Seven" group, or "Combine," that dominated the Prohibition era, for example, was composed of Charles "Lucky" Luciano, Joe Adonis, Waxey Gordon, Harry Rosen, Frank Costello, Longy Zwillman, and Nucky Johnson. Only three of the seven had Italian origins. In Chicago, Johnny Torrio and Al Capone were Italian, but their rivals Bugs Moran and Hymie Weiss were not.

Perhaps due to Capone's notoriety, the Italian gangster became highlighted in popular culture, with Little Caesar (1931) and Scarface (1932) featuring Italian-American gangsters, although The Public Enemy (1931) had Irish criminal protagonists.

The Italian Mafia became more of a pop culture fixture in the 1960s, after the Kefauver Committee (1950-1) raised public consciousness of the Mafia as an international criminal conspiracy, the abortive Apalachin meeting, and the 1963 testimony of former mobster Joseph Valachi revealed several details of Italian organized crime.

Mario Puzo's 1969 novel The Godfather, and the 1972 film adaptation, drew on Valachi's testimony for many aspects of mob life, such as the organization of the New York mob into five families, each with a parallel command structure, each headed by a "don" or "godfather." After Valachi, federal agents began using the term "La Cosa Nostra" ("our thing" in Italians) or LCN to refer to Italian organized crime, based on Valachi's terminology.

Needless to say, with the success of The Godfather, other pop culture representations followed suit, both in the United States and elsewhere (witness Monty Python's Piranha Brothers). But it was the revelations of the 1950s and 1960s, which turned organized crime from a local and somewhat humdrum institution to a shadowy, exotic international conspiracy that was likely responsible.