Experts believed Charles "Lucky" Luciano was the father of organised crime and hailed him as the model for legendary mafia boss Don Corleone, played by Marlon Brando in the Francis Ford Coppola movie based on the Mario Puzo book.
Luciano was widely credited for running New York's notorious underworld, and was linked to extortion rackets, punishment attacks and gangland murders. But according to new research, his reputation was largely fabricated by the US government to justify the expense of tracking him down.
The revelations emerge in a new book, Lucky Luciano: Mafia Murderer and Secret Agent - 74 years after his imprisonment, and 48 years after his death. US author Tim Newark said the claims will shock other biographers who had painted Lucky as the archetypal gangster.
Mr Newark said: "The myth of Lucky Luciano is incredible. For decades, he has been portrayed as the father of modern organised crime, no less. "But after delving into the archives, I realised the real Lucky was in some respects, a fake."
Luciano was born in Sicily, in 1897 but moved to New York at the age of ten to dabble in crime. But Mr Newark said: "The sad truth is Lucky was a has-been without the money or power to pull off what he was said to. Even if he had, the Mafia wouldn't have worked with him because of his very public reputation."
Thanks to Raanan Geberer