Victoria is the only Barkley who was never shot throughout the run of the series. Heath was shot the most, and Nick has the distinction of being the only Barkley who is shot twice in the same episode.

According to "Wildest Westerns Magazine", Peter Breck was able to draw his gun in 16/100 of a second, making the character of Nick Barkley the fastest draw in television history.

This was the only western to be built around a strong, female lead character.

There was originally a fourth Barkley son, Eugene Barkley, portrayed by Charles Briles, who appeared in eight episodes of the first season. Briles was forced to leave the show midway through the first season because in real life he was drafted by the U.S Army. After leaving the regular cast, Eugene never returned in later seasons, even when Briles mustered out of the Army, and basically, Eugene was never really referred to again.

The series was loosely based on the Hill Ranch, which was located on the western edge of Calaveras County in California. Lawson Hill started the ranch and ran it until his death in 1861. He and his wife Euphemia had four children, three sons and one daughter.

Dell Comics published a six-issue comic book series based on the series from 1966-69.

The series was canceled despite its popularity, because the networks were phasing out westerns in favor of more modern TV shows.

In every episode where Nick is a spectator in a court-case, he interrupts the court to speak his peace, which always gets him into trouble with the judge who is presiding. In later episodes throughout the series, this took on a comedic tone, as the viewer knew that it was only a matter of time before Nick would voice his displeasure.

With the February 6, 2012, death of Peter Breck (Nick) and the June 12, 2016 death of Charles Briles (Eugene; only eight appearances during the first season), there are only two regular or recurring cast members with more than 20 appearances on the show, Lee Majors (Heath) and Linda Evans (Audra Barkley).

Heath's horse was named Charger.

Richard Long's character Jarrod was the only one to ever get married; it only lasted a few days after only meeting a week before. She died accidentally taking a bullet for Jarrod when leaning over to pick a flower while picnicking beside a stream where their future home was going to be built.

The jailhouse set is the same one used in Gunsmoke (1955).

Victoria's horse was Misty Girl, while Nick rode Coco.

Of all of the leading actors of the show Barbara Stanwyck was the only one nominated for an Emmy. She was nominated during each of the first three seasons of the show and won her first nomination.

Linda Evans went over every Saturday to Barbara Stanwyck's house to work on the scenes together to the point where Linda began to think of Barbara as her mother.

The exterior shot of the Barkley house shown in the opening theme was also Tara, the same house exterior used in "Gone With The Wind,"

Throughout the series Lee Majors in the credits was always introduced as Heath, no last name. This was because, even though he was accepted as a member of the family, there was always the question of whether he was a true Barkley or not.