Arnold Rothstein might have been the inspiration for the Fats-Felson pool marathon in “The Hustler” and Nathan Detroit’s floating crap games from “Guys and Dolls.”
And George is based on Larry David and Elaine was based on several women in Seifelds life. But all the characters moved far away from their inspirations.
In the Godfather Moe Green is obviously based on Bugsy Segal and in GFII Hyman Roth is Meyer Lansky. Except Lansky died in his own bed.
Jack Aubrey in Patrick O’Brian’s books is at least partly based on Thomas Cochrane
Although Rand denied it, many people think The Fountainhead’s Howard Roark is based on Frank Lloyd Wright.
Popeye, believe it or not, was based on an old sailor E.C. Segar knew. He was named Frank “Rocky” Fiegel, and he really was a tough SOB who beat up the punks who annoyed him, according to Bud Sagendorf, who took over the strip after Segar’s death.
Here’s a picture (not the top one – scroll down)
Evil Eye Fleegle in “Li’l Abner” was based on Benjamin David ‘Evil Eye’ Finkel, a real-life hex man. You can actually see him in the doc Float Like a Butterfly, Sting Like a Bee (1969). Al Nesor played him in the movie and on-stage, I believe, and they both later moved to South Florida (and both previously lived in NYC). I have to imagine they met each other at some point.
Steve McQueen copied the mannerisms, style of dress, and quick-draw holster of SFPD inspector Dave Toschi for his character in Bullitt.
Haven’t been able to confirm it, but I’ve heard that Clint Eastwood based his character in the Dirty Harry films on Dave Toschi.
This theme was played up a little in the film Zodiac which had Mark Ruffalo playing Dave Toschi going to the premiere of Dirty Harry and walking out early bored out of his mind.
Auguste Piccard has two to his score. Jean-Luc has his name…
But Professor Calculus from Tintin is as near a twin as possible.
IIRC, when he was first introduced, he was supposed to actually be Hunter Thompson (or a charactature of him, anyways). “Duke” was a pen name of the real Thompson.
Over time, he’s more or less evolved into his own character though.