Vito Corleone is a composite of several real-life Dons:
--He was the top olive oil importer in the US, like Joe Profaci.
--He was the victor in a Mafia war in the early Thirties, and left his rival dead with bread in his mouth, like Salvatore Maranzano.
--He was grooming his son to become the new Don, like Joe Bonanno.
But he was most like Frank Costello: he "had all the judges in New York"; was the most politically powerful; was big in gambling and unions; frowned on drugs; retired after an unsuccessful assassination attempt, and died peacefully.