"Sinatra was convinced that Johnny Fontane, a mob-associated singer in Mario Puzo's novel The Godfather (1969), was based on his life. Puzo wrote in 1972 that when the author and singer met in Chasen's, Sinatra "started to shout abuse", calling Puzo a "pimp" and threatening physical violence. This was recreated in the miniseries The Offer with Sinatra portrayed by Frank John Hughes. Francis Ford Coppola, director of the film adaptation, said in the audio commentary that "Obviously Johnny Fontane was inspired by a kind of Frank Sinatra character".

https://en.wikipedia.org/wiki/Frank_Sinatra