When "Lucky" Luciano and the others bring in "Mad Dog" Coll to offer him a chance to move to California, they get into a discussion about Coll's style of killing, to which Coll slaps "Bugsy" Siegel on the knee and laughs out "There's nothing so pretty as the back of a man's head!" Ironically, when Bugsy Siegel was murdered in 1947, he was shot through the back of the head.
When Don Faranzano (His name was Maranzano in real life) is introducing his underbosses at the banquet where he announces himself as the "Boss of all bosses", he names the underbosses as "Lucky" Luciano, Joe Bonnano, Joe Profaci, Vincent Mangano, and Thomas Gagliano. After Lucky orchestrated the death of Faranzano/Maranzano in real life, the five underbosses became the heads of the individual "Five Families" of organized crime in New York. Eventually, through the years of succession, the Luciano family became the Genovese Family. The Mangano Family became the Gambino Family. The Gagliano family became the Luchese Family. And the Profaci Family became the Columbo Family. Only the Bonnano Family retained the name of it's original leader.