As mentioned above by some, the Vito Corleone character as well as some of the story was a compilation of several well known mobsters / real life events.

The wedding scene was most definitely based on the wedding of Bill & Rosalie Bonnano.

The story about Luca Brazi assisting Vito in getting Johnny out of a contract with a big time band leader is loosely based on Frank Sinatra and Tommy Dorsey. Real life gangster Willie Moretti was alleged to be the one who held a gun to the band leaders head.

Vito being the king of Olive Oil.....Joe Profaci
Vito's political connections.....Frank Costello
Vito being soft spoken and and low key......Carlo Gambino


Don Cardi cool

Five - ten years from now, they're gonna wish there was American Cosa Nostra. Five - ten years from now, they're gonna miss John Gotti.