James "Big Jim" Colosimo (February 1878 – May also known as "Diamond Jim" was an Italian-American Mafia crime boss who built a criminal empire in Chicago based on prostitution, gambling and racketeering.
Johnny Torrio, from Brooklyn, became the mob boss of Chicago after he arranged the killing of his uncle-through-marriage "Big Jim" Colosimo. Torrio brought Al Capone out to Chicago, and handed his empire to Capone after several attempts on Torrio's life.
Michael Genovese aka The Wiseman. The younger brother of Vito, the Family Head. He came to America in Eventually Michael became associated with his brother, running his Italian Lottery racket after Vito fled to Italy in Became a Naturalised Citizen in
Antonino Accardo (“Tony,” “Joe Batters,” “The Big Tuna”) – Remained as top Outfit consigliere until his death and approved every major decision that was made Tony Accardo ruled Chicago from the up until his death in the early RIP Tony!