It isn't often anymore that a show that generates decent or strong ratings doesn't return for another season.
Back in the early days of television, corporate sponsors controlled a lot of primetime shows, and if there was something they didn't like, they asked for the show to be cancelled, so long as the time slot could be refilled by another series they could get behind.
Such was the case with Johnny Ringo, the fictionalized account of a real life outlaw in the 19th century. Johnson Wax (now S. C. Johnson) was the sponsor, and decided they wanted a sitcom airing in Ringo's spot the next season, resulting in the series being cancelled when the network (CBS) couldn't find another spot and/or sponsor for it.
This itineration of Ringo came from the pen of no less than Aaron Spelling, who was just getting his feet wet in television. Spelling was commissioned by Dick Powell to develop the show for its star, actor-singer-songwriter Don Durant, who composed and sang the show's theme song, with the vocals playing over the closing credits.
In the series, Ringo was looking to leave his gunfighter past behind him and begin a new life. He's hired on as a sheriff in a small Arizona town overrun with corruption. This is all explained in the opener, "The Arrival", with James Coburn in an early role of his own.
Co-star Mark Goddard, of course, is better known for Lost in Space, and moved from Ringo to Robert Taylor's The Detectives.