Born Giovanni Narcchione in Cleveland, Nardi began his mob work as an enforcer for the local vending machine workers union.

He earned his first police record entry in 1939 at the age of twenty three, while employed by a vending workers union to sell the services of their repair technicians, at which he could be overly enthusiastic.

When Nardi threatened a bar owner with bodily harm, Safety Director Eliot Ness ordered him to be arrested.

Nardi also formed ties with "Jimmy the Weasel" Fratianno, a future boss with the Los Angeles crime family, with whom he also ran a bookmaking operation in Cleveland's Little Italy.

Not content to wait years to become a made man, or full member, of the organization, Nardi eventually stopped paying tribute to the family.

At the end of the 1976 festival, Nardi claimed that the Cleveland family owed him a share of the illegal gambling profits from that event.

Nardi and Greene had previously taken a trip to New York to discuss a partnership with Gambino crime family boss Paul Castellano about a meat business venture in Texas.

On May 17, 1977, in Cleveland, a bomb was placed in a car next to Nardi's vehicle in the rear of the parking lot of the Teamsters Joint Council 41, across from the musicians union.

In the 2011 film Kill the Irishman, John Nardi (Vincent D'Onofrio) is depicted as a made man and a caporegime rather than as an associate of the family.

Soon after Genovese boss Anthony Salerno (Paul Sorvino) sends Ray Ferritto (Robert Davi) from Los Angeles to Cleveland, Nardi is fatally injured by a car bomb moments after telling Greene that they will soon "take this town over."