Dodge City, Kansas was a notorious boomtown in the frontier days and generally considered not a nice place to be. Famous lawman Wyatt Earp served as an assistant marshal there, and the town was later mythologized in the radio and TV series Gunsmoke.
The phrase “get [the hell] out of Dodge” was popularized by James Arness who played marshal Matt Dillon on the TV show. Episodes would invariably end with the bad guys being run out of town.
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