This is another of those fondly remembered TV series from my childhood, a very short-lived (20 episodes total) Western about U.S. marshals bringing law and order to the Dakotas. The lead was someone named Larry Ward as Marshal Frank Ragan, and his three deputies were an impossibly young Chad Everett, an obscure actor named Michael Greene, and the real star of the show as far as me and most of my friends who watched it were concerned, the great Jack Elam as Deputy J.D. Smith. Elam is one of my favorite character actors, and his character in THE DAKOTAS started out as somewhat villainous, being a gunslinger who was hired to kill Marshal Ragan but wound up working for him instead. Definitely a Hipshot Percussion sort of character, and even though he was one of the good guys, he always had a borderline craziness about him. I suspect that one reason the series wasn't successful was that viewers in 1963 really didn't know what to make of Elam's character. The ten-year-old boys knew, though: he was cool.
The scripts were a bit odd, too, often starting in the middle of the action, and they were very violent for the time, to the point that controversy, along with low ratings, helped kill the series after less than a season. The episode in the YouTube clip below, "Sanctuary at Crystal Springs", prompted a lot of protests because its final shootout took place in a church.
Of course, I didn't really know much about any of that at the time. I just liked the show and was sorry when it went off the air. I didn't know that it was a spinoff from CHEYENNE, either (CHEYENNE being another favorite of mine from that era). As far as I know, THE DAKOTAS isn't available on DVD except maybe on the gray market, but it's one of those shows that ought to be.