Wyatt Earp was Inspiration for Matt Dillon
I'm a big Gunsmoke fan and have read just about everything I can get my hands on regarding that show.
Notice in this movie that Peter Graves (James Arness' brother) plays Morgan Earp, Wyatt's brother. Also in the end, Laurie's father, Mr. McCoy, talks about Wyatt "taking that job in Dodge City."
The fictional character of Matt Dillon, the U.S. Marshal in Dodge City in Gunsmoke, was based on Wyatt Earp. It's really funny though because in older pieces (around the radio show) you find this a lot, but at some point evidently the story was changed because in later articles (well into the run of the TV series) you find quotes telling a different story. I have also researched (Freemason) Wyatt Earp extensively and am convinced that Dillon was indeed based on Earp.