Widely regarded as the best TV western of all time, "Bonanza" ran for over 400 episodes from 1959 to 1973. It followed the adventures of Ben Cartwright (Lorne Greene) and his three sons, who run a ranch in the Nevada Territory in the 1860s. Their forthright dedication to fairness and law allow them to overcome all manner of challenges, which the show relayed with a winning mixture of drama and comedy.
"Gunsmoke" ran even longer than "Bonanza": 635 episodes from 1955 to 1975 on CBS. It followed the trail of Matt Dillon (James Arness), the marshal of Dodge City, Kan., as he attempted to keep the peace. It actually began as a radio show in 1952, and for the first 10 years of its run, it was broadcast in black and white. Its success helped launch a spate of television westerns that followed in its wake.
"Rawhide" debuted on CBS in 1959 and ran until 1966, comprising 217 episodes. It followed a group of drovers transporting cattle from Texas to Missouri. Each episode took place on the trail somewhere. Though moderately successful, it didn't match the popularity of "Gunsmoke" or "Bonanza." It is most famous for introducing the world to one of the most famous onscreen cowboys ever: Clint Eastwood, who played the full-of-beans drover Rowdy Yates on the show.
Not to be confused with the poorly regarded Will Smith movie, "Wild Wild West" started life as a television series that ran from 1965 to 1969. At that time, the genre had grown a little stale. "Wild Wild West" attempted to shake things up by introducing "steampunk" gadgets and James Bond-style disguises to the mix. Its two heroes--James West (Robert Conrad) and Artemus Gordon (Ross Martin)--are U.S. Secret Service agents, who travel the country in a modified train stopping plots against the government.
Like "Wild Wild West," "Maverick" sought to deconstruct the TV western a bit. It concerned the escapades of a pair of gambling brothers--Bret and Bart Maverick--who were cut from a significantly different cloth than most cowboy heroes. They played outside the rules, they preferred to avoid fights when possible, and they often did the right thing by default rather than by intention. The show ran from 1957 until 1962 and made a star out of James Garner, who played Bret.